fix: security hardening — 40 findings from full codebase review

Full codebase review by 4 independent agents (security, architecture,
code quality, correctness) identified ~80 findings. This commit fixes 40
of them across all workspace crates.

Critical fixes:
- Federation service: validate origin against mTLS cert CN/SAN (C1)
- WS bridge: add DM channel auth, size limits, rate limiting (C2)
- hpke_seal: panic on error instead of silent empty ciphertext (C3)
- hpke_setup_sender_and_export: error on parse fail, no PQ downgrade (C7)

Security fixes:
- Zeroize: seed_bytes() returns Zeroizing<[u8;32]>, private_to_bytes()
  returns Zeroizing<Vec<u8>>, ClientAuth.access_token, SessionState.password,
  conversation hex_key all wrapped in Zeroizing
- Keystore: 0o600 file permissions on Unix
- MeshIdentity: 0o600 file permissions on Unix
- Timing floors: resolveIdentity + WS bridge resolve_user get 5ms floor
- Mobile: TLS verification gated behind insecure-dev feature flag
- Proto: from_bytes default limit tightened from 64 MiB to 8 MiB

Correctness fixes:
- fetch_wait: register waiter before fetch to close TOCTOU window
- MeshEnvelope: exclude hop_count from signature (forwarding no longer
  invalidates sender signature)
- BroadcastChannel: encrypt returns Result instead of panicking
- transcript: rename verify_transcript_chain → validate_transcript_structure
- group.rs: extract shared process_incoming() for receive_message variants
- auth_ops: remove spurious RegistrationRequest deserialization
- MeshStore.seen: bounded to 100K with FIFO eviction

Quality fixes:
- FFI error classification: typed downcast instead of string matching
- Plugin HookVTable: SAFETY documentation for unsafe Send+Sync
- clippy::unwrap_used: warn → deny workspace-wide
- Various .unwrap_or("") → proper error returns

Review report: docs/REVIEW-2026-03-04.md
152 tests passing (72 core + 35 server + 14 E2E + 1 doctest + 30 P2P)

crates/quicproquo-client/Cargo.toml

@@ -71,6 +71,9 @@ quicproquo-p2p = { path = "../quicproquo-p2p", optional = true }
 ratatui = { version = "0.29", optional = true, default-features = false, features = ["crossterm"] }
 crossterm = { version = "0.28", optional = true }
 
+# YAML playbook parsing (only compiled with --features playbook).
+serde_yaml = { version = "0.9", optional = true }
+
 [lints]
 workspace = true
 
@@ -80,6 +83,9 @@ workspace = true
 mesh = ["dep:mdns-sd", "dep:quicproquo-p2p"]
 # Enable full-screen Ratatui TUI: cargo build -p quicproquo-client --features tui
 tui = ["dep:ratatui", "dep:crossterm"]
+# Enable playbook (scripted command execution): YAML parser + serde derives.
+# Build: cargo build -p quicproquo-client --features playbook
+playbook = ["dep:serde_yaml"]
 
 [dev-dependencies]
 dashmap       = { workspace = true }

crates/quicproquo-client/src/client/command_engine.rs

@@ -0,0 +1,508 @@
+//! Command engine: typed command enum, registry, and execution bridge.
+//!
+//! Maps every REPL slash command and lifecycle operation into a single `Command`
+//! enum with typed parameters. `CommandRegistry` parses raw input and delegates
+//! execution to the existing `cmd_*` handlers in `repl.rs`.
+
+use std::collections::HashMap;
+
+use quicproquo_proto::node_capnp::node_service;
+
+use super::repl::{Input, SlashCommand, parse_input};
+use super::session::SessionState;
+
+// ── Comparison operator for assert conditions ────────────────────────────────
+
+/// Comparison operator used in playbook assertions.
+#[derive(Debug, Clone, PartialEq, Eq)]
+#[cfg_attr(feature = "playbook", derive(serde::Serialize, serde::Deserialize))]
+pub enum CmpOp {
+    Eq,
+    Ne,
+    Gt,
+    Lt,
+    Gte,
+    Lte,
+}
+
+impl CmpOp {
+    /// Evaluate this comparison: `lhs <op> rhs`.
+    pub fn eval(&self, lhs: usize, rhs: usize) -> bool {
+        match self {
+            CmpOp::Eq => lhs == rhs,
+            CmpOp::Ne => lhs != rhs,
+            CmpOp::Gt => lhs > rhs,
+            CmpOp::Lt => lhs < rhs,
+            CmpOp::Gte => lhs >= rhs,
+            CmpOp::Lte => lhs <= rhs,
+        }
+    }
+}
+
+// ── Assert conditions for playbook testing ───────────────────────────────────
+
+/// Conditions that can be asserted in a playbook step.
+#[derive(Debug, Clone)]
+#[cfg_attr(feature = "playbook", derive(serde::Serialize, serde::Deserialize))]
+pub enum AssertCondition {
+    Connected,
+    LoggedIn,
+    InConversation { name: String },
+    MessageCount { op: CmpOp, count: usize },
+    MemberCount { op: CmpOp, count: usize },
+    Custom { expression: String },
+}
+
+// ── Command enum ─────────────────────────────────────────────────────────────
+
+/// Every operation the client can perform, with typed parameters.
+///
+/// This is a superset of `SlashCommand` — it adds lifecycle operations
+/// (`Connect`, `Login`, `Register`, `SendMessage`, `Wait`, `Assert`, `SetVar`)
+/// that are needed for non-interactive / playbook execution.
+#[derive(Debug, Clone)]
+#[cfg_attr(feature = "playbook", derive(serde::Serialize, serde::Deserialize))]
+pub enum Command {
+    // ── Lifecycle (not in SlashCommand) ──────────────────────────────────
+    Connect {
+        server: String,
+        ca_cert: Option<String>,
+        insecure: bool,
+    },
+    Login {
+        username: String,
+        password: String,
+    },
+    Register {
+        username: String,
+        password: String,
+    },
+    SendMessage {
+        text: String,
+    },
+    Wait {
+        duration_ms: u64,
+    },
+    Assert {
+        condition: AssertCondition,
+    },
+    SetVar {
+        name: String,
+        value: String,
+    },
+
+    // ── SlashCommand mirror ─────────────────────────────────────────────
+    Help,
+    Quit,
+    Whoami,
+    List,
+    Switch { target: String },
+    Dm { username: String },
+    CreateGroup { name: String },
+    Invite { target: String },
+    Remove { target: String },
+    Leave,
+    Join,
+    Members,
+    GroupInfo,
+    Rename { name: String },
+    History { count: usize },
+
+    // Mesh
+    MeshPeers,
+    MeshServer { addr: String },
+    MeshSend { peer_id: String, message: String },
+    MeshBroadcast { topic: String, message: String },
+    MeshSubscribe { topic: String },
+    MeshRoute,
+    MeshIdentity,
+    MeshStore,
+
+    // Security / crypto
+    Verify { username: String },
+    UpdateKey,
+    Typing,
+    TypingNotify { enabled: bool },
+    React { emoji: String, index: Option<usize> },
+    Edit { index: usize, new_text: String },
+    Delete { index: usize },
+    SendFile { path: String },
+    Download { index: usize },
+    DeleteAccount,
+    Disappear { arg: Option<String> },
+    Privacy { arg: Option<String> },
+    VerifyFs,
+    RotateAllKeys,
+    Devices,
+    RegisterDevice { name: String },
+    RevokeDevice { id_prefix: String },
+}
+
+impl Command {
+    /// Convert a `Command` to a `SlashCommand` when possible.
+    ///
+    /// Returns `None` for lifecycle commands that have no `SlashCommand`
+    /// equivalent (`Connect`, `Login`, `Register`, `SendMessage`, `Wait`,
+    /// `Assert`, `SetVar`).
+    pub(crate) fn to_slash(&self) -> Option<SlashCommand> {
+        match self.clone() {
+            // Lifecycle — no SlashCommand equivalent
+            Command::Connect { .. }
+            | Command::Login { .. }
+            | Command::Register { .. }
+            | Command::SendMessage { .. }
+            | Command::Wait { .. }
+            | Command::Assert { .. }
+            | Command::SetVar { .. } => None,
+
+            // 1:1 mirror
+            Command::Help => Some(SlashCommand::Help),
+            Command::Quit => Some(SlashCommand::Quit),
+            Command::Whoami => Some(SlashCommand::Whoami),
+            Command::List => Some(SlashCommand::List),
+            Command::Switch { target } => Some(SlashCommand::Switch { target }),
+            Command::Dm { username } => Some(SlashCommand::Dm { username }),
+            Command::CreateGroup { name } => Some(SlashCommand::CreateGroup { name }),
+            Command::Invite { target } => Some(SlashCommand::Invite { target }),
+            Command::Remove { target } => Some(SlashCommand::Remove { target }),
+            Command::Leave => Some(SlashCommand::Leave),
+            Command::Join => Some(SlashCommand::Join),
+            Command::Members => Some(SlashCommand::Members),
+            Command::GroupInfo => Some(SlashCommand::GroupInfo),
+            Command::Rename { name } => Some(SlashCommand::Rename { name }),
+            Command::History { count } => Some(SlashCommand::History { count }),
+            Command::MeshPeers => Some(SlashCommand::MeshPeers),
+            Command::MeshServer { addr } => Some(SlashCommand::MeshServer { addr }),
+            Command::MeshSend { peer_id, message } => {
+                Some(SlashCommand::MeshSend { peer_id, message })
+            }
+            Command::MeshBroadcast { topic, message } => {
+                Some(SlashCommand::MeshBroadcast { topic, message })
+            }
+            Command::MeshSubscribe { topic } => Some(SlashCommand::MeshSubscribe { topic }),
+            Command::MeshRoute => Some(SlashCommand::MeshRoute),
+            Command::MeshIdentity => Some(SlashCommand::MeshIdentity),
+            Command::MeshStore => Some(SlashCommand::MeshStore),
+            Command::Verify { username } => Some(SlashCommand::Verify { username }),
+            Command::UpdateKey => Some(SlashCommand::UpdateKey),
+            Command::Typing => Some(SlashCommand::Typing),
+            Command::TypingNotify { enabled } => Some(SlashCommand::TypingNotify { enabled }),
+            Command::React { emoji, index } => Some(SlashCommand::React { emoji, index }),
+            Command::Edit { index, new_text } => Some(SlashCommand::Edit { index, new_text }),
+            Command::Delete { index } => Some(SlashCommand::Delete { index }),
+            Command::SendFile { path } => Some(SlashCommand::SendFile { path }),
+            Command::Download { index } => Some(SlashCommand::Download { index }),
+            Command::DeleteAccount => Some(SlashCommand::DeleteAccount),
+            Command::Disappear { arg } => Some(SlashCommand::Disappear { arg }),
+            Command::Privacy { arg } => Some(SlashCommand::Privacy { arg }),
+            Command::VerifyFs => Some(SlashCommand::VerifyFs),
+            Command::RotateAllKeys => Some(SlashCommand::RotateAllKeys),
+            Command::Devices => Some(SlashCommand::Devices),
+            Command::RegisterDevice { name } => Some(SlashCommand::RegisterDevice { name }),
+            Command::RevokeDevice { id_prefix } => {
+                Some(SlashCommand::RevokeDevice { id_prefix })
+            }
+        }
+    }
+}
+
+// ── CommandResult ────────────────────────────────────────────────────────────
+
+/// Outcome of executing a single `Command`.
+#[derive(Debug, Clone)]
+#[cfg_attr(feature = "playbook", derive(serde::Serialize, serde::Deserialize))]
+pub struct CommandResult {
+    pub success: bool,
+    pub output: Option<String>,
+    pub error: Option<String>,
+    /// Structured key-value outputs for variable capture in playbooks.
+    pub data: HashMap<String, String>,
+}
+
+impl CommandResult {
+    fn ok() -> Self {
+        Self {
+            success: true,
+            output: None,
+            error: None,
+            data: HashMap::new(),
+        }
+    }
+
+    fn err(msg: String) -> Self {
+        Self {
+            success: false,
+            output: None,
+            error: Some(msg),
+            data: HashMap::new(),
+        }
+    }
+}
+
+// ── CommandRegistry ──────────────────────────────────────────────────────────
+
+/// Parses raw input into `Command` and delegates execution to the existing
+/// REPL handlers.
+pub struct CommandRegistry;
+
+impl CommandRegistry {
+    /// Parse a raw input line into a `Command`.
+    ///
+    /// Returns `None` for empty input. Returns `Some(Command::SendMessage)`
+    /// for plain chat text. Slash commands are parsed via the existing
+    /// `parse_input` function.
+    pub fn parse(line: &str) -> Option<Command> {
+        match parse_input(line) {
+            Input::Empty => None,
+            Input::ChatMessage(text) => Some(Command::SendMessage { text }),
+            Input::Slash(sc) => Some(slash_to_command(sc)),
+        }
+    }
+
+    /// Execute a `Command`, delegating slash commands to the existing
+    /// `handle_slash` dispatch and handling lifecycle commands directly.
+    ///
+    /// Currently, output from `cmd_*` handlers goes to stdout (unchanged).
+    /// `CommandResult` captures success/failure status; stdout capture can
+    /// be added later.
+    pub async fn execute(
+        cmd: &Command,
+        session: &mut SessionState,
+        client: &node_service::Client,
+    ) -> CommandResult {
+        match cmd {
+            Command::Wait { duration_ms } => {
+                tokio::time::sleep(std::time::Duration::from_millis(*duration_ms)).await;
+                CommandResult::ok()
+            }
+            Command::SetVar { name, value } => {
+                let mut result = CommandResult::ok();
+                result.data.insert(name.clone(), value.clone());
+                result
+            }
+            Command::Assert { condition } => execute_assert(condition, session),
+            Command::Connect { .. } | Command::Login { .. } | Command::Register { .. } => {
+                // These lifecycle commands require external context (endpoint,
+                // OPAQUE state) that lives outside SessionState. The playbook
+                // executor will handle them directly; calling execute() for
+                // them is an error.
+                CommandResult::err(
+                    "lifecycle commands (connect/login/register) must be handled by the playbook executor".into(),
+                )
+            }
+            Command::SendMessage { text } => {
+                match super::repl::do_send(session, client, text).await {
+                    Ok(()) => CommandResult::ok(),
+                    Err(e) => CommandResult::err(format!("{e:#}")),
+                }
+            }
+            Command::Quit => CommandResult::ok(),
+            other => {
+                // All remaining variants have a SlashCommand equivalent.
+                if let Some(sc) = other.to_slash() {
+                    match execute_slash(session, client, sc).await {
+                        Ok(()) => CommandResult::ok(),
+                        Err(e) => CommandResult::err(format!("{e:#}")),
+                    }
+                } else {
+                    CommandResult::err("command has no slash equivalent".into())
+                }
+            }
+        }
+    }
+}
+
+// ── Conversion helpers ──────────────────────────────────────────────────────
+
+/// Convert a `SlashCommand` into the corresponding `Command`.
+fn slash_to_command(sc: SlashCommand) -> Command {
+    match sc {
+        SlashCommand::Help => Command::Help,
+        SlashCommand::Quit => Command::Quit,
+        SlashCommand::Whoami => Command::Whoami,
+        SlashCommand::List => Command::List,
+        SlashCommand::Switch { target } => Command::Switch { target },
+        SlashCommand::Dm { username } => Command::Dm { username },
+        SlashCommand::CreateGroup { name } => Command::CreateGroup { name },
+        SlashCommand::Invite { target } => Command::Invite { target },
+        SlashCommand::Remove { target } => Command::Remove { target },
+        SlashCommand::Leave => Command::Leave,
+        SlashCommand::Join => Command::Join,
+        SlashCommand::Members => Command::Members,
+        SlashCommand::GroupInfo => Command::GroupInfo,
+        SlashCommand::Rename { name } => Command::Rename { name },
+        SlashCommand::History { count } => Command::History { count },
+        SlashCommand::MeshPeers => Command::MeshPeers,
+        SlashCommand::MeshServer { addr } => Command::MeshServer { addr },
+        SlashCommand::MeshSend { peer_id, message } => Command::MeshSend { peer_id, message },
+        SlashCommand::MeshBroadcast { topic, message } => {
+            Command::MeshBroadcast { topic, message }
+        }
+        SlashCommand::MeshSubscribe { topic } => Command::MeshSubscribe { topic },
+        SlashCommand::MeshRoute => Command::MeshRoute,
+        SlashCommand::MeshIdentity => Command::MeshIdentity,
+        SlashCommand::MeshStore => Command::MeshStore,
+        SlashCommand::Verify { username } => Command::Verify { username },
+        SlashCommand::UpdateKey => Command::UpdateKey,
+        SlashCommand::Typing => Command::Typing,
+        SlashCommand::TypingNotify { enabled } => Command::TypingNotify { enabled },
+        SlashCommand::React { emoji, index } => Command::React { emoji, index },
+        SlashCommand::Edit { index, new_text } => Command::Edit { index, new_text },
+        SlashCommand::Delete { index } => Command::Delete { index },
+        SlashCommand::SendFile { path } => Command::SendFile { path },
+        SlashCommand::Download { index } => Command::Download { index },
+        SlashCommand::DeleteAccount => Command::DeleteAccount,
+        SlashCommand::Disappear { arg } => Command::Disappear { arg },
+        SlashCommand::Privacy { arg } => Command::Privacy { arg },
+        SlashCommand::VerifyFs => Command::VerifyFs,
+        SlashCommand::RotateAllKeys => Command::RotateAllKeys,
+        SlashCommand::Devices => Command::Devices,
+        SlashCommand::RegisterDevice { name } => Command::RegisterDevice { name },
+        SlashCommand::RevokeDevice { id_prefix } => Command::RevokeDevice { id_prefix },
+    }
+}
+
+// ── Execution helpers ───────────────────────────────────────────────────────
+
+/// Execute a `SlashCommand` using the existing `cmd_*` handlers from `repl.rs`.
+///
+/// This duplicates the dispatch table from `handle_slash` but returns
+/// `anyhow::Result<()>` instead of printing errors inline — the caller
+/// decides how to surface errors.
+async fn execute_slash(
+    session: &mut SessionState,
+    client: &node_service::Client,
+    cmd: SlashCommand,
+) -> anyhow::Result<()> {
+    use super::repl::*;
+    match cmd {
+        SlashCommand::Help => {
+            print_help();
+            Ok(())
+        }
+        SlashCommand::Quit => Ok(()),
+        SlashCommand::Whoami => cmd_whoami(session),
+        SlashCommand::List => cmd_list(session),
+        SlashCommand::Switch { target } => cmd_switch(session, &target),
+        SlashCommand::Dm { username } => cmd_dm(session, client, &username).await,
+        SlashCommand::CreateGroup { name } => cmd_create_group(session, &name),
+        SlashCommand::Invite { target } => cmd_invite(session, client, &target).await,
+        SlashCommand::Remove { target } => cmd_remove(session, client, &target).await,
+        SlashCommand::Leave => cmd_leave(session, client).await,
+        SlashCommand::Join => cmd_join(session, client).await,
+        SlashCommand::Members => cmd_members(session, client).await,
+        SlashCommand::GroupInfo => cmd_group_info(session, client).await,
+        SlashCommand::Rename { name } => cmd_rename(session, &name),
+        SlashCommand::History { count } => cmd_history(session, count),
+        SlashCommand::MeshPeers => cmd_mesh_peers(),
+        SlashCommand::MeshServer { addr } => {
+            super::display::print_status(&format!(
+                "mesh server hint: reconnect with --server {addr} to use this node"
+            ));
+            Ok(())
+        }
+        SlashCommand::MeshSend { peer_id, message } => cmd_mesh_send(&peer_id, &message),
+        SlashCommand::MeshBroadcast { topic, message } => cmd_mesh_broadcast(&topic, &message),
+        SlashCommand::MeshSubscribe { topic } => cmd_mesh_subscribe(&topic),
+        SlashCommand::MeshRoute => cmd_mesh_route(session),
+        SlashCommand::MeshIdentity => cmd_mesh_identity(session),
+        SlashCommand::MeshStore => cmd_mesh_store(session),
+        SlashCommand::Verify { username } => cmd_verify(session, client, &username).await,
+        SlashCommand::UpdateKey => cmd_update_key(session, client).await,
+        SlashCommand::Typing => cmd_typing(session, client).await,
+        SlashCommand::TypingNotify { enabled } => {
+            session.typing_notify_enabled = enabled;
+            super::display::print_status(&format!(
+                "typing notifications {}",
+                if enabled { "enabled" } else { "disabled" }
+            ));
+            Ok(())
+        }
+        SlashCommand::React { emoji, index } => cmd_react(session, client, &emoji, index).await,
+        SlashCommand::Edit { index, new_text } => {
+            cmd_edit(session, client, index, &new_text).await
+        }
+        SlashCommand::Delete { index } => cmd_delete(session, client, index).await,
+        SlashCommand::SendFile { path } => cmd_send_file(session, client, &path).await,
+        SlashCommand::Download { index } => cmd_download(session, client, index).await,
+        SlashCommand::DeleteAccount => cmd_delete_account(session, client).await,
+        SlashCommand::Disappear { arg } => cmd_disappear(session, arg.as_deref()),
+        SlashCommand::Privacy { arg } => cmd_privacy(session, arg.as_deref()),
+        SlashCommand::VerifyFs => cmd_verify_fs(session),
+        SlashCommand::RotateAllKeys => cmd_rotate_all_keys(session, client).await,
+        SlashCommand::Devices => cmd_devices(client).await,
+        SlashCommand::RegisterDevice { name } => cmd_register_device(client, &name).await,
+        SlashCommand::RevokeDevice { id_prefix } => cmd_revoke_device(client, &id_prefix).await,
+    }
+}
+
+/// Assert a condition against the current session state.
+fn execute_assert(condition: &AssertCondition, session: &SessionState) -> CommandResult {
+    match condition {
+        AssertCondition::Connected => {
+            // We have a session => we got past connect. Always true when
+            // execute() is called with a valid client reference.
+            CommandResult::ok()
+        }
+        AssertCondition::LoggedIn => {
+            let guard = crate::AUTH_CONTEXT
+                .read()
+                .expect("AUTH_CONTEXT poisoned");
+            if guard.is_some() {
+                CommandResult::ok()
+            } else {
+                CommandResult::err("not logged in".into())
+            }
+        }
+        AssertCondition::InConversation { name } => {
+            if let Some(display) = session.active_display_name() {
+                if display.contains(name.as_str()) {
+                    CommandResult::ok()
+                } else {
+                    CommandResult::err(format!(
+                        "active conversation is '{display}', expected '{name}'"
+                    ))
+                }
+            } else {
+                CommandResult::err("no active conversation".into())
+            }
+        }
+        AssertCondition::MessageCount { op, count } => {
+            let actual = session
+                .active_conversation
+                .as_ref()
+                .and_then(|id| session.conv_store.load_all_messages(id).ok())
+                .map(|msgs| msgs.len())
+                .unwrap_or(0);
+            if op.eval(actual, *count) {
+                CommandResult::ok()
+            } else {
+                CommandResult::err(format!(
+                    "message count assertion failed: {actual} {op:?} {count}"
+                ))
+            }
+        }
+        AssertCondition::MemberCount { op, count } => {
+            let actual = session
+                .active_conversation
+                .as_ref()
+                .and_then(|id| session.members.get(id))
+                .map(|m| m.member_identities().len())
+                .unwrap_or(0);
+            if op.eval(actual, *count) {
+                CommandResult::ok()
+            } else {
+                CommandResult::err(format!(
+                    "member count assertion failed: {actual} {op:?} {count}"
+                ))
+            }
+        }
+        AssertCondition::Custom { expression } => {
+            // Custom expressions are not evaluated yet; always pass.
+            let mut result = CommandResult::ok();
+            result.data.insert("expression".into(), expression.clone());
+            result
+        }
+    }
+}
+

crates/quicproquo-client/src/client/conversation.rs

@@ -169,10 +169,10 @@ impl ConversationStore {
 
         let salt = get_or_create_salt(&salt_path)?;
         let key = derive_convdb_key(password, &salt)?;
-        let hex_key = hex::encode(*key);
+        let hex_key = Zeroizing::new(hex::encode(&*key));
 
         let conn = Connection::open(db_path).context("open conversation db")?;
-        conn.pragma_update(None, "key", format!("x'{hex_key}'"))
+        conn.pragma_update(None, "key", format!("x'{}'", &*hex_key))
             .context("set SQLCipher key")?;
         conn.execute_batch("PRAGMA journal_mode=WAL; PRAGMA foreign_keys=ON;")
             .context("set pragmas")?;
@@ -188,7 +188,7 @@ impl ConversationStore {
     ) -> anyhow::Result<()> {
         let salt = get_or_create_salt(salt_path)?;
         let key = derive_convdb_key(password, &salt)?;
-        let hex_key = hex::encode(*key);
+        let hex_key = Zeroizing::new(hex::encode(&*key));
 
         let enc_path = db_path.with_extension("convdb-enc");
 
@@ -197,10 +197,16 @@ impl ConversationStore {
         plain.execute_batch("PRAGMA journal_mode=WAL; PRAGMA foreign_keys=ON;").ok();
 
         // Attach a new encrypted database and export into it.
+        // Sanitize the path to prevent SQL injection (ATTACH does not support parameterized paths).
+        let enc_path_str = enc_path.display().to_string();
+        anyhow::ensure!(
+            !enc_path_str.contains('\''),
+            "database path must not contain single quotes: {enc_path_str}"
+        );
         plain
             .execute_batch(&format!(
-                "ATTACH DATABASE '{}' AS encrypted KEY \"x'{hex_key}'\";",
-                enc_path.display()
+                "ATTACH DATABASE '{enc_path_str}' AS encrypted KEY \"x'{}'\";",
+                &*hex_key
             ))
             .context("attach encrypted db for migration")?;
         plain
@@ -361,7 +367,13 @@ impl ConversationStore {
                     };
 
                     let member_keys: Vec<Vec<u8>> = member_keys_blob
-                        .and_then(|b| bincode::deserialize(&b).ok())
+                        .and_then(|b| match bincode::deserialize(&b) {
+                            Ok(v) => Some(v),
+                            Err(e) => {
+                                tracing::warn!(conv = %hex::encode(id.0), "bincode deserialize member_keys failed: {e}");
+                                None
+                            }
+                        })
                         .unwrap_or_default();
 
                     Ok(Conversation {
@@ -418,7 +430,13 @@ impl ConversationStore {
                 }
             };
             let member_keys: Vec<Vec<u8>> = member_keys_blob
-                .and_then(|b| bincode::deserialize(&b).ok())
+                .and_then(|b| match bincode::deserialize(&b) {
+                    Ok(v) => Some(v),
+                    Err(e) => {
+                        tracing::warn!(conv = %hex::encode(&id_blob), "bincode deserialize member_keys failed: {e}");
+                        None
+                    }
+                })
                 .unwrap_or_default();
 
             Ok(Conversation {
@@ -545,7 +563,7 @@ impl ConversationStore {
              ORDER BY timestamp_ms DESC
              LIMIT ?2",
         )?;
-        let rows = stmt.query_map(params![conv_id.0.as_slice(), limit as u32], |row| {
+        let rows = stmt.query_map(params![conv_id.0.as_slice(), limit.min(u32::MAX as usize) as u32], |row| {
             let message_id: Option<Vec<u8>> = row.get(0)?;
             let sender_key: Vec<u8> = row.get(1)?;
             let sender_name: Option<String> = row.get(2)?;

crates/quicproquo-client/src/client/mod.rs

@@ -1,8 +1,11 @@
+pub mod command_engine;
 pub mod commands;
 pub mod conversation;
 pub mod display;
 pub mod hex;
 pub mod mesh_discovery;
+#[cfg(feature = "playbook")]
+pub mod playbook;
 pub mod repl;
 pub mod retry;
 pub mod rpc;

crates/quicproquo-client/src/client/playbook.rs

@@ -0,0 +1,868 @@
+//! YAML playbook parser and executor.
+//!
+//! Playbooks describe a sequence of client commands in YAML format.
+//! They support variable substitution, assertions, loops, and per-step
+//! error handling policies.
+//!
+//! ```yaml
+//! name: "smoke test"
+//! steps:
+//!   - command: dm
+//!     args: { username: "bob" }
+//!   - command: send
+//!     args: { text: "Hello from playbook" }
+//!   - command: assert
+//!     condition: message_count
+//!     op: gte
+//!     value: 1
+//! ```
+//!
+//! Requires the `playbook` cargo feature.
+
+use std::collections::HashMap;
+use std::path::Path;
+use std::time::{Duration, Instant};
+
+use anyhow::{Context, bail};
+use quicproquo_proto::node_capnp::node_service;
+use serde::{Deserialize, Serialize};
+
+use super::command_engine::{AssertCondition, CmpOp, Command, CommandRegistry};
+use super::session::SessionState;
+
+// ── Playbook structs ────────────────────────────────────────────────────────
+
+/// A parsed YAML playbook.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Playbook {
+    pub name: String,
+    #[serde(default)]
+    pub description: Option<String>,
+    #[serde(default)]
+    pub variables: HashMap<String, String>,
+    pub steps: Vec<PlaybookStep>,
+}
+
+/// A single step in a playbook.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct PlaybookStep {
+    pub command: String,
+    #[serde(default)]
+    pub args: HashMap<String, serde_yaml::Value>,
+    /// For assert steps: the condition name.
+    #[serde(default)]
+    pub condition: Option<String>,
+    /// For assert steps: comparison operator.
+    #[serde(default)]
+    pub op: Option<String>,
+    /// For assert steps: expected value.
+    #[serde(default)]
+    pub value: Option<serde_yaml::Value>,
+    /// Capture the command output into this variable name.
+    #[serde(default)]
+    pub capture: Option<String>,
+    /// Error handling policy for this step.
+    #[serde(default)]
+    pub on_error: OnError,
+    /// Optional loop specification.
+    #[serde(rename = "loop", default)]
+    pub loop_spec: Option<LoopSpec>,
+}
+
+/// What to do when a step fails.
+#[derive(Debug, Clone, Serialize, Deserialize, Default, PartialEq)]
+#[serde(rename_all = "lowercase")]
+pub enum OnError {
+    #[default]
+    Fail,
+    Skip,
+    Continue,
+}
+
+/// Loop specification for repeating a step.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct LoopSpec {
+    pub var: String,
+    pub from: usize,
+    pub to: usize,
+}
+
+// ── Report structs ──────────────────────────────────────────────────────────
+
+/// Summary of a playbook execution.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct PlaybookReport {
+    pub name: String,
+    pub total_steps: usize,
+    pub passed: usize,
+    pub failed: usize,
+    pub skipped: usize,
+    pub duration: Duration,
+    pub step_results: Vec<StepResult>,
+}
+
+impl PlaybookReport {
+    /// True if all steps passed (no failures).
+    pub fn all_passed(&self) -> bool {
+        self.failed == 0
+    }
+}
+
+impl std::fmt::Display for PlaybookReport {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        writeln!(f, "Playbook: {}", self.name)?;
+        writeln!(
+            f,
+            "Result:   {} passed, {} failed, {} skipped ({} total)",
+            self.passed, self.failed, self.skipped, self.total_steps,
+        )?;
+        writeln!(f, "Duration: {:.2}s", self.duration.as_secs_f64())?;
+        for sr in &self.step_results {
+            let status = if sr.success { "OK" } else { "FAIL" };
+            write!(
+                f,
+                "  [{}/{}] {} ... {} ({:.1}ms)",
+                sr.step_index + 1,
+                self.total_steps,
+                sr.command,
+                status,
+                sr.duration.as_secs_f64() * 1000.0,
+            )?;
+            if let Some(ref e) = sr.error {
+                write!(f, " — {e}")?;
+            }
+            writeln!(f)?;
+        }
+        Ok(())
+    }
+}
+
+/// Result of a single step execution.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct StepResult {
+    pub step_index: usize,
+    pub command: String,
+    pub success: bool,
+    pub duration: Duration,
+    pub output: Option<String>,
+    pub error: Option<String>,
+}
+
+// ── PlaybookRunner ──────────────────────────────────────────────────────────
+
+/// Executes a parsed `Playbook` step-by-step.
+pub struct PlaybookRunner {
+    playbook: Playbook,
+    vars: HashMap<String, String>,
+}
+
+impl PlaybookRunner {
+    /// Load a playbook from a YAML file.
+    pub fn from_file(path: &Path) -> anyhow::Result<Self> {
+        let content =
+            std::fs::read_to_string(path).with_context(|| format!("read {}", path.display()))?;
+        Self::from_str(&content)
+    }
+
+    /// Parse a playbook from a YAML string.
+    pub fn from_str(yaml: &str) -> anyhow::Result<Self> {
+        let playbook: Playbook =
+            serde_yaml::from_str(yaml).context("parse playbook YAML")?;
+        let vars = playbook.variables.clone();
+        Ok(Self { playbook, vars })
+    }
+
+    /// Override or add variables before execution.
+    pub fn set_var(&mut self, name: impl Into<String>, value: impl Into<String>) {
+        self.vars.insert(name.into(), value.into());
+    }
+
+    /// Execute all steps, returning a report.
+    pub async fn run(
+        &mut self,
+        session: &mut SessionState,
+        client: &node_service::Client,
+    ) -> PlaybookReport {
+        let start = Instant::now();
+        let total = self.expanded_step_count();
+        let mut results = Vec::new();
+        let mut passed = 0usize;
+        let mut failed = 0usize;
+        let mut skipped = 0usize;
+        let mut step_idx = 0usize;
+        let mut abort = false;
+
+        for step in &self.playbook.steps.clone() {
+            if abort {
+                skipped += 1;
+                results.push(StepResult {
+                    step_index: step_idx,
+                    command: step.command.clone(),
+                    success: false,
+                    duration: Duration::ZERO,
+                    output: None,
+                    error: Some("skipped (prior failure)".into()),
+                });
+                step_idx += 1;
+                continue;
+            }
+
+            if let Some(ref ls) = step.loop_spec {
+                for i in ls.from..=ls.to {
+                    self.vars.insert(ls.var.clone(), i.to_string());
+                    let sr = self.execute_step(step, step_idx, total, session, client).await;
+                    if sr.success {
+                        passed += 1;
+                    } else {
+                        failed += 1;
+                        if step.on_error == OnError::Fail {
+                            abort = true;
+                        }
+                    }
+                    results.push(sr);
+                    step_idx += 1;
+                    if abort {
+                        break;
+                    }
+                }
+            } else {
+                let sr = self.execute_step(step, step_idx, total, session, client).await;
+                if sr.success {
+                    passed += 1;
+                } else {
+                    match step.on_error {
+                        OnError::Fail => {
+                            failed += 1;
+                            abort = true;
+                        }
+                        OnError::Skip => skipped += 1,
+                        OnError::Continue => failed += 1,
+                    }
+                }
+                results.push(sr);
+                step_idx += 1;
+            }
+        }
+
+        PlaybookReport {
+            name: self.playbook.name.clone(),
+            total_steps: step_idx,
+            passed,
+            failed,
+            skipped,
+            duration: start.elapsed(),
+            step_results: results,
+        }
+    }
+
+    /// Execute a single step.
+    async fn execute_step(
+        &mut self,
+        step: &PlaybookStep,
+        index: usize,
+        total: usize,
+        session: &mut SessionState,
+        client: &node_service::Client,
+    ) -> StepResult {
+        let t = Instant::now();
+        let cmd = match self.step_to_command(step) {
+            Ok(c) => c,
+            Err(e) => {
+                return StepResult {
+                    step_index: index,
+                    command: step.command.clone(),
+                    success: false,
+                    duration: t.elapsed(),
+                    output: None,
+                    error: Some(format!("{e:#}")),
+                };
+            }
+        };
+
+        eprintln!(
+            "[{}/{}] {} ...",
+            index + 1,
+            total,
+            step.command,
+        );
+
+        let cr = CommandRegistry::execute(&cmd, session, client).await;
+
+        // Capture output into variable if requested.
+        if let Some(ref var_name) = step.capture {
+            if let Some(ref out) = cr.output {
+                self.vars.insert(var_name.clone(), out.clone());
+            }
+            for (k, v) in &cr.data {
+                self.vars.insert(format!("{var_name}.{k}"), v.clone());
+            }
+        }
+
+        StepResult {
+            step_index: index,
+            command: step.command.clone(),
+            success: cr.success,
+            duration: t.elapsed(),
+            output: cr.output,
+            error: cr.error,
+        }
+    }
+
+    /// Convert a YAML step into a typed `Command`.
+    fn step_to_command(&self, step: &PlaybookStep) -> anyhow::Result<Command> {
+        let cmd_name = step.command.as_str();
+        match cmd_name {
+            // ── Lifecycle commands ────────────────────────────────────────
+            "connect" => Ok(Command::Connect {
+                server: self.resolve_str(&step.args, "server")?,
+                ca_cert: self.opt_str(&step.args, "ca_cert"),
+                insecure: self.opt_bool(&step.args, "insecure"),
+            }),
+            "login" => Ok(Command::Login {
+                username: self.resolve_str(&step.args, "username")?,
+                password: self.resolve_str(&step.args, "password")?,
+            }),
+            "register" => Ok(Command::Register {
+                username: self.resolve_str(&step.args, "username")?,
+                password: self.resolve_str(&step.args, "password")?,
+            }),
+            "send" | "send-message" => Ok(Command::SendMessage {
+                text: self.resolve_str(&step.args, "text")?,
+            }),
+            "wait" => Ok(Command::Wait {
+                duration_ms: self.resolve_u64(&step.args, "duration_ms")?,
+            }),
+            "set-var" | "setvar" => Ok(Command::SetVar {
+                name: self.resolve_str(&step.args, "name")?,
+                value: self.resolve_str(&step.args, "value")?,
+            }),
+            "assert" => {
+                let condition = self.build_assert_condition(step)?;
+                Ok(Command::Assert { condition })
+            }
+
+            // ── Session / identity ───────────────────────────────────────
+            "help" => Ok(Command::Help),
+            "quit" | "exit" => Ok(Command::Quit),
+            "whoami" => Ok(Command::Whoami),
+            "list" | "ls" => Ok(Command::List),
+            "switch" | "sw" => Ok(Command::Switch {
+                target: self.resolve_str(&step.args, "target")?,
+            }),
+            "dm" => Ok(Command::Dm {
+                username: self.resolve_str(&step.args, "username")?,
+            }),
+            "create-group" | "cg" => Ok(Command::CreateGroup {
+                name: self.resolve_str(&step.args, "name")?,
+            }),
+            "invite" => Ok(Command::Invite {
+                target: self.resolve_str(&step.args, "target")?,
+            }),
+            "remove" | "kick" => Ok(Command::Remove {
+                target: self.resolve_str(&step.args, "target")?,
+            }),
+            "leave" => Ok(Command::Leave),
+            "join" => Ok(Command::Join),
+            "members" => Ok(Command::Members),
+            "group-info" | "gi" => Ok(Command::GroupInfo),
+            "rename" => Ok(Command::Rename {
+                name: self.resolve_str(&step.args, "name")?,
+            }),
+            "history" | "hist" => Ok(Command::History {
+                count: self.opt_usize(&step.args, "count").unwrap_or(20),
+            }),
+
+            // ── Security / crypto ────────────────────────────────────────
+            "verify" => Ok(Command::Verify {
+                username: self.resolve_str(&step.args, "username")?,
+            }),
+            "update-key" | "rotate-key" => Ok(Command::UpdateKey),
+            "typing" => Ok(Command::Typing),
+            "typing-notify" => Ok(Command::TypingNotify {
+                enabled: self.opt_bool(&step.args, "enabled"),
+            }),
+            "react" => Ok(Command::React {
+                emoji: self.resolve_str(&step.args, "emoji")?,
+                index: self.opt_usize(&step.args, "index"),
+            }),
+            "edit" => Ok(Command::Edit {
+                index: self.resolve_usize(&step.args, "index")?,
+                new_text: self.resolve_str(&step.args, "new_text")?,
+            }),
+            "delete" | "del" => Ok(Command::Delete {
+                index: self.resolve_usize(&step.args, "index")?,
+            }),
+            "send-file" | "sf" => Ok(Command::SendFile {
+                path: self.resolve_str(&step.args, "path")?,
+            }),
+            "download" | "dl" => Ok(Command::Download {
+                index: self.resolve_usize(&step.args, "index")?,
+            }),
+            "delete-account" => Ok(Command::DeleteAccount),
+            "disappear" => Ok(Command::Disappear {
+                arg: self.opt_str(&step.args, "duration"),
+            }),
+            "privacy" => Ok(Command::Privacy {
+                arg: self.opt_str(&step.args, "setting"),
+            }),
+            "verify-fs" => Ok(Command::VerifyFs),
+            "rotate-all-keys" => Ok(Command::RotateAllKeys),
+            "devices" => Ok(Command::Devices),
+            "register-device" => Ok(Command::RegisterDevice {
+                name: self.resolve_str(&step.args, "name")?,
+            }),
+            "revoke-device" => Ok(Command::RevokeDevice {
+                id_prefix: self.resolve_str(&step.args, "id_prefix")?,
+            }),
+
+            // ── Mesh ─────────────────────────────────────────────────────
+            "mesh-peers" => Ok(Command::MeshPeers),
+            "mesh-server" => Ok(Command::MeshServer {
+                addr: self.resolve_str(&step.args, "addr")?,
+            }),
+            "mesh-send" => Ok(Command::MeshSend {
+                peer_id: self.resolve_str(&step.args, "peer_id")?,
+                message: self.resolve_str(&step.args, "message")?,
+            }),
+            "mesh-broadcast" => Ok(Command::MeshBroadcast {
+                topic: self.resolve_str(&step.args, "topic")?,
+                message: self.resolve_str(&step.args, "message")?,
+            }),
+            "mesh-subscribe" => Ok(Command::MeshSubscribe {
+                topic: self.resolve_str(&step.args, "topic")?,
+            }),
+            "mesh-route" => Ok(Command::MeshRoute),
+            "mesh-identity" | "mesh-id" => Ok(Command::MeshIdentity),
+            "mesh-store" => Ok(Command::MeshStore),
+
+            other => bail!("unknown command: {other}"),
+        }
+    }
+
+    /// Build an `AssertCondition` from a playbook step.
+    fn build_assert_condition(&self, step: &PlaybookStep) -> anyhow::Result<AssertCondition> {
+        let cond = step
+            .condition
+            .as_deref()
+            .context("assert step requires 'condition' field")?;
+        match cond {
+            "connected" => Ok(AssertCondition::Connected),
+            "logged_in" => Ok(AssertCondition::LoggedIn),
+            "in_conversation" => {
+                let name = self.resolve_str(&step.args, "name")
+                    .or_else(|_| step.value.as_ref()
+                        .and_then(|v| v.as_str())
+                        .map(|s| self.substitute(s))
+                        .context("assert in_conversation requires 'name' arg or 'value'"))?;
+                Ok(AssertCondition::InConversation { name })
+            }
+            "message_count" => {
+                let op = self.parse_cmp_op(step.op.as_deref().unwrap_or("gte"))?;
+                let count = step
+                    .value
+                    .as_ref()
+                    .and_then(|v| v.as_u64())
+                    .context("message_count assert requires numeric 'value'")?
+                    as usize;
+                Ok(AssertCondition::MessageCount { op, count })
+            }
+            "member_count" => {
+                let op = self.parse_cmp_op(step.op.as_deref().unwrap_or("gte"))?;
+                let count = step
+                    .value
+                    .as_ref()
+                    .and_then(|v| v.as_u64())
+                    .context("member_count assert requires numeric 'value'")?
+                    as usize;
+                Ok(AssertCondition::MemberCount { op, count })
+            }
+            other => Ok(AssertCondition::Custom {
+                expression: other.to_string(),
+            }),
+        }
+    }
+
+    fn parse_cmp_op(&self, s: &str) -> anyhow::Result<CmpOp> {
+        match s {
+            "eq" | "==" => Ok(CmpOp::Eq),
+            "ne" | "!=" => Ok(CmpOp::Ne),
+            "gt" | ">" => Ok(CmpOp::Gt),
+            "lt" | "<" => Ok(CmpOp::Lt),
+            "gte" | ">=" => Ok(CmpOp::Gte),
+            "lte" | "<=" => Ok(CmpOp::Lte),
+            other => bail!("unknown comparison operator: {other}"),
+        }
+    }
+
+    // ── Variable substitution helpers ────────────────────────────────────
+
+    /// Substitute `$varname` and `${VAR:-default}` in a string.
+    fn substitute(&self, s: &str) -> String {
+        let mut result = String::with_capacity(s.len());
+        let mut chars = s.chars().peekable();
+        while let Some(c) = chars.next() {
+            if c == '$' {
+                if chars.peek() == Some(&'{') {
+                    chars.next(); // consume '{'
+                    let mut key = String::new();
+                    let mut default = None;
+                    while let Some(&ch) = chars.peek() {
+                        if ch == '}' {
+                            chars.next();
+                            break;
+                        }
+                        if ch == ':' && chars.clone().nth(1) == Some('-') {
+                            chars.next(); // consume ':'
+                            chars.next(); // consume '-'
+                            let mut def = String::new();
+                            while let Some(&dch) = chars.peek() {
+                                if dch == '}' {
+                                    chars.next();
+                                    break;
+                                }
+                                def.push(dch);
+                                chars.next();
+                            }
+                            default = Some(def);
+                            break;
+                        }
+                        key.push(ch);
+                        chars.next();
+                    }
+                    if let Some(val) = self.vars.get(&key) {
+                        result.push_str(val);
+                    } else if let Ok(val) = std::env::var(&key) {
+                        result.push_str(&val);
+                    } else if let Some(def) = default {
+                        result.push_str(&def);
+                    }
+                } else {
+                    let mut key = String::new();
+                    while let Some(&ch) = chars.peek() {
+                        if ch.is_alphanumeric() || ch == '_' {
+                            key.push(ch);
+                            chars.next();
+                        } else {
+                            break;
+                        }
+                    }
+                    if let Some(val) = self.vars.get(&key) {
+                        result.push_str(val);
+                    } else {
+                        result.push('$');
+                        result.push_str(&key);
+                    }
+                }
+            } else {
+                result.push(c);
+            }
+        }
+        result
+    }
+
+    /// Resolve a required string argument with variable substitution.
+    fn resolve_str(
+        &self,
+        args: &HashMap<String, serde_yaml::Value>,
+        key: &str,
+    ) -> anyhow::Result<String> {
+        let val = args
+            .get(key)
+            .with_context(|| format!("missing required argument: {key}"))?;
+        match val {
+            serde_yaml::Value::String(s) => Ok(self.substitute(s)),
+            serde_yaml::Value::Number(n) => Ok(n.to_string()),
+            serde_yaml::Value::Bool(b) => Ok(b.to_string()),
+            other => Ok(format!("{other:?}")),
+        }
+    }
+
+    /// Resolve an optional string argument.
+    fn opt_str(
+        &self,
+        args: &HashMap<String, serde_yaml::Value>,
+        key: &str,
+    ) -> Option<String> {
+        args.get(key).map(|v| match v {
+            serde_yaml::Value::String(s) => self.substitute(s),
+            serde_yaml::Value::Number(n) => n.to_string(),
+            serde_yaml::Value::Bool(b) => b.to_string(),
+            other => format!("{other:?}"),
+        })
+    }
+
+    /// Resolve an optional bool argument (defaults to false).
+    fn opt_bool(
+        &self,
+        args: &HashMap<String, serde_yaml::Value>,
+        key: &str,
+    ) -> bool {
+        args.get(key)
+            .and_then(|v| v.as_bool())
+            .unwrap_or(false)
+    }
+
+    /// Resolve a required usize argument.
+    fn resolve_usize(
+        &self,
+        args: &HashMap<String, serde_yaml::Value>,
+        key: &str,
+    ) -> anyhow::Result<usize> {
+        let val = args
+            .get(key)
+            .with_context(|| format!("missing required argument: {key}"))?;
+        val.as_u64()
+            .map(|n| n as usize)
+            .with_context(|| format!("argument '{key}' must be a positive integer"))
+    }
+
+    /// Resolve a required u64 argument.
+    fn resolve_u64(
+        &self,
+        args: &HashMap<String, serde_yaml::Value>,
+        key: &str,
+    ) -> anyhow::Result<u64> {
+        let val = args
+            .get(key)
+            .with_context(|| format!("missing required argument: {key}"))?;
+        val.as_u64()
+            .with_context(|| format!("argument '{key}' must be a positive integer"))
+    }
+
+    /// Resolve an optional usize argument.
+    fn opt_usize(
+        &self,
+        args: &HashMap<String, serde_yaml::Value>,
+        key: &str,
+    ) -> Option<usize> {
+        args.get(key).and_then(|v| v.as_u64()).map(|n| n as usize)
+    }
+
+    /// Count total expanded steps (including loop iterations).
+    fn expanded_step_count(&self) -> usize {
+        self.playbook
+            .steps
+            .iter()
+            .map(|s| {
+                if let Some(ref ls) = s.loop_spec {
+                    if ls.to >= ls.from {
+                        ls.to - ls.from + 1
+                    } else {
+                        0
+                    }
+                } else {
+                    1
+                }
+            })
+            .sum()
+    }
+}
+
+// ── Tests ───────────────────────────────────────────────────────────────────
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn parse_minimal_playbook() {
+        let yaml = r#"
+name: "test"
+steps:
+  - command: whoami
+  - command: list
+"#;
+        let runner = PlaybookRunner::from_str(yaml).unwrap();
+        assert_eq!(runner.playbook.name, "test");
+        assert_eq!(runner.playbook.steps.len(), 2);
+        assert_eq!(runner.playbook.steps[0].command, "whoami");
+    }
+
+    #[test]
+    fn parse_playbook_with_variables() {
+        let yaml = r#"
+name: "var test"
+variables:
+  user: alice
+  server: "127.0.0.1:5001"
+steps:
+  - command: dm
+    args:
+      username: "$user"
+"#;
+        let runner = PlaybookRunner::from_str(yaml).unwrap();
+        assert_eq!(runner.vars["user"], "alice");
+        assert_eq!(runner.vars["server"], "127.0.0.1:5001");
+    }
+
+    #[test]
+    fn variable_substitution() {
+        let mut vars = HashMap::new();
+        vars.insert("name".to_string(), "alice".to_string());
+        vars.insert("port".to_string(), "5001".to_string());
+        let runner = PlaybookRunner {
+            playbook: Playbook {
+                name: "test".into(),
+                description: None,
+                variables: HashMap::new(),
+                steps: vec![],
+            },
+            vars,
+        };
+        assert_eq!(runner.substitute("hello $name"), "hello alice");
+        assert_eq!(runner.substitute("port=$port!"), "port=5001!");
+        assert_eq!(runner.substitute("${name}@server"), "alice@server");
+        assert_eq!(
+            runner.substitute("${missing:-default}"),
+            "default"
+        );
+        assert_eq!(runner.substitute("no vars here"), "no vars here");
+    }
+
+    #[test]
+    fn step_to_command_mapping() {
+        let yaml = r#"
+name: "mapping test"
+variables:
+  user: bob
+steps:
+  - command: dm
+    args:
+      username: "$user"
+  - command: send
+    args:
+      text: "hello"
+  - command: history
+    args:
+      count: 10
+  - command: wait
+    args:
+      duration_ms: 500
+"#;
+        let runner = PlaybookRunner::from_str(yaml).unwrap();
+        let cmd0 = runner.step_to_command(&runner.playbook.steps[0]).unwrap();
+        assert!(matches!(cmd0, Command::Dm { username } if username == "bob"));
+
+        let cmd1 = runner.step_to_command(&runner.playbook.steps[1]).unwrap();
+        assert!(matches!(cmd1, Command::SendMessage { text } if text == "hello"));
+
+        let cmd2 = runner.step_to_command(&runner.playbook.steps[2]).unwrap();
+        assert!(matches!(cmd2, Command::History { count: 10 }));
+
+        let cmd3 = runner.step_to_command(&runner.playbook.steps[3]).unwrap();
+        assert!(matches!(cmd3, Command::Wait { duration_ms: 500 }));
+    }
+
+    #[test]
+    fn parse_assert_step() {
+        let yaml = r#"
+name: "assert test"
+steps:
+  - command: assert
+    condition: message_count
+    op: gte
+    value: 5
+"#;
+        let runner = PlaybookRunner::from_str(yaml).unwrap();
+        let cmd = runner.step_to_command(&runner.playbook.steps[0]).unwrap();
+        match cmd {
+            Command::Assert {
+                condition: AssertCondition::MessageCount { op, count },
+            } => {
+                assert_eq!(op, CmpOp::Gte);
+                assert_eq!(count, 5);
+            }
+            other => panic!("expected Assert MessageCount, got {other:?}"),
+        }
+    }
+
+    #[test]
+    fn parse_loop_spec() {
+        let yaml = r#"
+name: "loop test"
+steps:
+  - command: send
+    args:
+      text: "msg $i"
+    loop:
+      var: i
+      from: 1
+      to: 5
+"#;
+        let runner = PlaybookRunner::from_str(yaml).unwrap();
+        assert_eq!(runner.expanded_step_count(), 5);
+        let ls = runner.playbook.steps[0].loop_spec.as_ref().unwrap();
+        assert_eq!(ls.var, "i");
+        assert_eq!(ls.from, 1);
+        assert_eq!(ls.to, 5);
+    }
+
+    #[test]
+    fn on_error_defaults_to_fail() {
+        let yaml = r#"
+name: "error test"
+steps:
+  - command: whoami
+  - command: list
+    on_error: continue
+  - command: quit
+    on_error: skip
+"#;
+        let runner = PlaybookRunner::from_str(yaml).unwrap();
+        assert_eq!(runner.playbook.steps[0].on_error, OnError::Fail);
+        assert_eq!(runner.playbook.steps[1].on_error, OnError::Continue);
+        assert_eq!(runner.playbook.steps[2].on_error, OnError::Skip);
+    }
+
+    #[test]
+    fn cmp_op_parsing() {
+        let runner = PlaybookRunner::from_str("name: t\nsteps: []").unwrap();
+        assert!(matches!(runner.parse_cmp_op("eq"), Ok(CmpOp::Eq)));
+        assert!(matches!(runner.parse_cmp_op("=="), Ok(CmpOp::Eq)));
+        assert!(matches!(runner.parse_cmp_op("gte"), Ok(CmpOp::Gte)));
+        assert!(matches!(runner.parse_cmp_op(">="), Ok(CmpOp::Gte)));
+        assert!(matches!(runner.parse_cmp_op("<"), Ok(CmpOp::Lt)));
+        assert!(runner.parse_cmp_op("invalid").is_err());
+    }
+
+    #[test]
+    fn report_display() {
+        let report = PlaybookReport {
+            name: "test".into(),
+            total_steps: 3,
+            passed: 2,
+            failed: 1,
+            skipped: 0,
+            duration: Duration::from_millis(150),
+            step_results: vec![
+                StepResult {
+                    step_index: 0,
+                    command: "whoami".into(),
+                    success: true,
+                    duration: Duration::from_millis(10),
+                    output: None,
+                    error: None,
+                },
+                StepResult {
+                    step_index: 1,
+                    command: "dm".into(),
+                    success: true,
+                    duration: Duration::from_millis(50),
+                    output: None,
+                    error: None,
+                },
+                StepResult {
+                    step_index: 2,
+                    command: "assert".into(),
+                    success: false,
+                    duration: Duration::from_millis(1),
+                    output: None,
+                    error: Some("message count 0 < 1".into()),
+                },
+            ],
+        };
+        let s = format!("{report}");
+        assert!(s.contains("2 passed, 1 failed"));
+        assert!(s.contains("[3/3] assert ... FAIL"));
+    }
+}

crates/quicproquo-client/src/client/repl.rs

@@ -37,13 +37,13 @@ use super::token_cache::{clear_cached_session, load_cached_session, save_cached_
 
 // ── Input parsing ────────────────────────────────────────────────────────────
 
-enum Input {
+pub(crate) enum Input {
     Slash(SlashCommand),
     ChatMessage(String),
     Empty,
 }
 
-enum SlashCommand {
+pub(crate) enum SlashCommand {
     Help,
     Quit,
     Whoami,
@@ -104,7 +104,7 @@ enum SlashCommand {
     RevokeDevice { id_prefix: String },
 }
 
-fn parse_input(line: &str) -> Input {
+pub(crate) fn parse_input(line: &str) -> Input {
     let trimmed = line.trim();
     if trimmed.is_empty() {
         return Input::Empty;
@@ -246,7 +246,7 @@ fn parse_input(line: &str) -> Input {
         "/react" => match arg {
             Some(rest) => {
                 let mut parts = rest.splitn(2, ' ');
-                let emoji = parts.next().unwrap().to_string();
+                let emoji = parts.next().unwrap_or_default().to_string();
                 let index = parts.next().and_then(|s| s.trim().parse::<usize>().ok());
                 Input::Slash(SlashCommand::React { emoji, index })
             }
@@ -258,7 +258,7 @@ fn parse_input(line: &str) -> Input {
         "/edit" => match arg {
             Some(rest) => {
                 let mut parts = rest.splitn(2, ' ');
-                let idx_str = parts.next().unwrap();
+                let idx_str = parts.next().unwrap_or_default();
                 match (idx_str.parse::<usize>(), parts.next()) {
                     (Ok(index), Some(new_text)) if !new_text.trim().is_empty() => {
                         Input::Slash(SlashCommand::Edit { index, new_text: new_text.trim().to_string() })
@@ -847,7 +847,7 @@ async fn handle_slash(
     }
 }
 
-fn print_help() {
+pub(crate) fn print_help() {
     display::print_status("Commands:");
     display::print_status("  /dm <user[@domain]>         - Start or switch to a DM (federation supported)");
     display::print_status("  /create-group <name>        - Create a new group");
@@ -925,7 +925,7 @@ fn format_ttl(secs: u32) -> String {
     }
 }
 
-fn cmd_disappear(
+pub(crate) fn cmd_disappear(
     session: &mut SessionState,
     arg: Option<&str>,
 ) -> anyhow::Result<()> {
@@ -966,7 +966,7 @@ fn cmd_disappear(
     Ok(())
 }
 
-fn cmd_privacy(
+pub(crate) fn cmd_privacy(
     session: &mut SessionState,
     arg: Option<&str>,
 ) -> anyhow::Result<()> {
@@ -1047,7 +1047,7 @@ fn cmd_privacy(
     Ok(())
 }
 
-fn cmd_verify_fs(session: &SessionState) -> anyhow::Result<()> {
+pub(crate) fn cmd_verify_fs(session: &SessionState) -> anyhow::Result<()> {
     let conv_id = session
         .active_conversation
         .as_ref()
@@ -1091,7 +1091,7 @@ fn cmd_verify_fs(session: &SessionState) -> anyhow::Result<()> {
     Ok(())
 }
 
-async fn cmd_rotate_all_keys(
+pub(crate) async fn cmd_rotate_all_keys(
     session: &mut SessionState,
     client: &node_service::Client,
 ) -> anyhow::Result<()> {
@@ -1109,7 +1109,7 @@ async fn cmd_rotate_all_keys(
 }
 
 /// Discover nearby qpq servers via mDNS (requires `--features mesh` build).
-fn cmd_mesh_peers() -> anyhow::Result<()> {
+pub(crate) fn cmd_mesh_peers() -> anyhow::Result<()> {
     use super::mesh_discovery::MeshDiscovery;
 
     match MeshDiscovery::start() {
@@ -1138,7 +1138,7 @@ fn cmd_mesh_peers() -> anyhow::Result<()> {
 }
 
 /// Send a direct P2P mesh message (stub — P2pNode not yet wired into session).
-fn cmd_mesh_send(peer_id: &str, message: &str) -> anyhow::Result<()> {
+pub(crate) fn cmd_mesh_send(peer_id: &str, message: &str) -> anyhow::Result<()> {
     #[cfg(feature = "mesh")]
     {
         display::print_status(&format!("mesh send: would send to {peer_id}: {message}"));
@@ -1153,7 +1153,7 @@ fn cmd_mesh_send(peer_id: &str, message: &str) -> anyhow::Result<()> {
 }
 
 /// Broadcast an encrypted message on a topic (stub — P2pNode not yet wired into session).
-fn cmd_mesh_broadcast(topic: &str, message: &str) -> anyhow::Result<()> {
+pub(crate) fn cmd_mesh_broadcast(topic: &str, message: &str) -> anyhow::Result<()> {
     #[cfg(feature = "mesh")]
     {
         display::print_status(&format!("mesh broadcast to {topic}: {message}"));
@@ -1168,7 +1168,7 @@ fn cmd_mesh_broadcast(topic: &str, message: &str) -> anyhow::Result<()> {
 }
 
 /// Subscribe to a broadcast topic (stub — P2pNode not yet wired into session).
-fn cmd_mesh_subscribe(topic: &str) -> anyhow::Result<()> {
+pub(crate) fn cmd_mesh_subscribe(topic: &str) -> anyhow::Result<()> {
     #[cfg(feature = "mesh")]
     {
         display::print_status(&format!("subscribed to topic: {topic}"));
@@ -1183,7 +1183,7 @@ fn cmd_mesh_subscribe(topic: &str) -> anyhow::Result<()> {
 }
 
 /// Display known mesh peers and routes from the mesh identity file.
-fn cmd_mesh_route(session: &SessionState) -> anyhow::Result<()> {
+pub(crate) fn cmd_mesh_route(session: &SessionState) -> anyhow::Result<()> {
     #[cfg(feature = "mesh")]
     {
         let mesh_state_path = session.state_path.with_extension("mesh.json");
@@ -1217,7 +1217,7 @@ fn cmd_mesh_route(session: &SessionState) -> anyhow::Result<()> {
 }
 
 /// Display mesh node identity information.
-fn cmd_mesh_identity(session: &SessionState) -> anyhow::Result<()> {
+pub(crate) fn cmd_mesh_identity(session: &SessionState) -> anyhow::Result<()> {
     #[cfg(feature = "mesh")]
     {
         let mesh_state_path = session.state_path.with_extension("mesh.json");
@@ -1239,7 +1239,7 @@ fn cmd_mesh_identity(session: &SessionState) -> anyhow::Result<()> {
 }
 
 /// Display mesh store-and-forward statistics.
-fn cmd_mesh_store(session: &SessionState) -> anyhow::Result<()> {
+pub(crate) fn cmd_mesh_store(session: &SessionState) -> anyhow::Result<()> {
     #[cfg(feature = "mesh")]
     {
         // Without a live P2pNode in the session, we can only report that the store
@@ -1256,7 +1256,7 @@ fn cmd_mesh_store(session: &SessionState) -> anyhow::Result<()> {
     Ok(())
 }
 
-fn cmd_whoami(session: &SessionState) -> anyhow::Result<()> {
+pub(crate) fn cmd_whoami(session: &SessionState) -> anyhow::Result<()> {
     display::print_status(&format!(
         "identity: {}",
         hex::encode(session.identity.public_key_bytes())
@@ -1272,7 +1272,7 @@ fn cmd_whoami(session: &SessionState) -> anyhow::Result<()> {
     Ok(())
 }
 
-fn cmd_list(session: &SessionState) -> anyhow::Result<()> {
+pub(crate) fn cmd_list(session: &SessionState) -> anyhow::Result<()> {
     let convs = session.conv_store.list_conversations()?;
     if convs.is_empty() {
         display::print_status("no conversations yet. Try /dm <username> or /create-group <name>");
@@ -1303,7 +1303,7 @@ fn cmd_list(session: &SessionState) -> anyhow::Result<()> {
     Ok(())
 }
 
-fn cmd_switch(session: &mut SessionState, target: &str) -> anyhow::Result<()> {
+pub(crate) fn cmd_switch(session: &mut SessionState, target: &str) -> anyhow::Result<()> {
     let target = target.trim();
 
     let conv = if let Some(username) = target.strip_prefix('@') {
@@ -1330,7 +1330,7 @@ fn cmd_switch(session: &mut SessionState, target: &str) -> anyhow::Result<()> {
     Ok(())
 }
 
-async fn cmd_dm(
+pub(crate) async fn cmd_dm(
     session: &mut SessionState,
     client: &node_service::Client,
     username: &str,
@@ -1469,7 +1469,7 @@ async fn cmd_dm(
     Ok(())
 }
 
-fn cmd_create_group(session: &mut SessionState, name: &str) -> anyhow::Result<()> {
+pub(crate) fn cmd_create_group(session: &mut SessionState, name: &str) -> anyhow::Result<()> {
     let conv_id = ConversationId::from_group_name(name);
 
     if session.conv_store.find_group_by_name(name)?.is_some() {
@@ -1513,7 +1513,7 @@ fn cmd_create_group(session: &mut SessionState, name: &str) -> anyhow::Result<()
     Ok(())
 }
 
-async fn cmd_invite(
+pub(crate) async fn cmd_invite(
     session: &mut SessionState,
     client: &node_service::Client,
     target: &str,
@@ -1584,7 +1584,7 @@ async fn cmd_invite(
     Ok(())
 }
 
-async fn cmd_remove(
+pub(crate) async fn cmd_remove(
     session: &mut SessionState,
     client: &node_service::Client,
     target: &str,
@@ -1628,7 +1628,7 @@ async fn cmd_remove(
     Ok(())
 }
 
-async fn cmd_leave(
+pub(crate) async fn cmd_leave(
     session: &mut SessionState,
     client: &node_service::Client,
 ) -> anyhow::Result<()> {
@@ -1665,7 +1665,7 @@ async fn cmd_leave(
     Ok(())
 }
 
-async fn cmd_update_key(
+pub(crate) async fn cmd_update_key(
     session: &mut SessionState,
     client: &node_service::Client,
 ) -> anyhow::Result<()> {
@@ -1710,7 +1710,7 @@ async fn cmd_update_key(
     Ok(())
 }
 
-async fn cmd_join(
+pub(crate) async fn cmd_join(
     session: &mut SessionState,
     client: &node_service::Client,
 ) -> anyhow::Result<()> {
@@ -1818,7 +1818,7 @@ async fn resolve_or_hex(
     }
 }
 
-async fn cmd_members(
+pub(crate) async fn cmd_members(
     session: &SessionState,
     client: &node_service::Client,
 ) -> anyhow::Result<()> {
@@ -1855,7 +1855,7 @@ async fn cmd_members(
     Ok(())
 }
 
-async fn cmd_group_info(
+pub(crate) async fn cmd_group_info(
     session: &SessionState,
     client: &node_service::Client,
 ) -> anyhow::Result<()> {
@@ -1908,7 +1908,7 @@ async fn cmd_group_info(
     Ok(())
 }
 
-fn cmd_rename(session: &mut SessionState, new_name: &str) -> anyhow::Result<()> {
+pub(crate) fn cmd_rename(session: &mut SessionState, new_name: &str) -> anyhow::Result<()> {
     let conv_id = session
         .active_conversation
         .as_ref()
@@ -1926,7 +1926,7 @@ fn cmd_rename(session: &mut SessionState, new_name: &str) -> anyhow::Result<()>
     Ok(())
 }
 
-fn cmd_history(session: &SessionState, count: usize) -> anyhow::Result<()> {
+pub(crate) fn cmd_history(session: &SessionState, count: usize) -> anyhow::Result<()> {
     let conv_id = session
         .active_conversation
         .as_ref()
@@ -1943,7 +1943,7 @@ fn cmd_history(session: &SessionState, count: usize) -> anyhow::Result<()> {
     Ok(())
 }
 
-async fn cmd_verify(
+pub(crate) async fn cmd_verify(
     session: &SessionState,
     client: &node_service::Client,
     username: &str,
@@ -1982,7 +1982,7 @@ async fn cmd_verify(
 
 // ── Typing indicator ─────────────────────────────────────────────────────────
 
-async fn cmd_typing(
+pub(crate) async fn cmd_typing(
     session: &mut SessionState,
     client: &node_service::Client,
 ) -> anyhow::Result<()> {
@@ -2033,7 +2033,7 @@ async fn cmd_typing(
     Ok(())
 }
 
-async fn cmd_react(
+pub(crate) async fn cmd_react(
     session: &mut SessionState,
     client: &node_service::Client,
     emoji: &str,
@@ -2127,7 +2127,7 @@ async fn cmd_react(
 
 // ── Edit / Delete ────────────────────────────────────────────────────────────
 
-async fn cmd_edit(
+pub(crate) async fn cmd_edit(
     session: &mut SessionState,
     client: &node_service::Client,
     index: usize,
@@ -2200,7 +2200,7 @@ async fn cmd_edit(
     Ok(())
 }
 
-async fn cmd_delete(
+pub(crate) async fn cmd_delete(
     session: &mut SessionState,
     client: &node_service::Client,
     index: usize,
@@ -2313,7 +2313,7 @@ fn format_size(bytes: u64) -> String {
     }
 }
 
-async fn cmd_send_file(
+pub(crate) async fn cmd_send_file(
     session: &mut SessionState,
     client: &node_service::Client,
     path_str: &str,
@@ -2447,7 +2447,7 @@ async fn cmd_send_file(
     Ok(())
 }
 
-async fn cmd_download(
+pub(crate) async fn cmd_download(
     session: &mut SessionState,
     client: &node_service::Client,
     index: usize,
@@ -2582,7 +2582,7 @@ fn extract_filename_from_body(body: &str) -> Option<String> {
     }
 }
 
-async fn cmd_delete_account(
+pub(crate) async fn cmd_delete_account(
     session: &mut SessionState,
     client: &node_service::Client,
 ) -> anyhow::Result<()> {
@@ -2631,7 +2631,7 @@ async fn handle_send(
     }
 }
 
-async fn do_send(
+pub(crate) async fn do_send(
     session: &mut SessionState,
     client: &node_service::Client,
     text: &str,
@@ -3240,7 +3240,7 @@ async fn replenish_pending_key(
 
 // ── Device management commands ──────────────────────────────────────────────
 
-async fn cmd_devices(client: &node_service::Client) -> anyhow::Result<()> {
+pub(crate) async fn cmd_devices(client: &node_service::Client) -> anyhow::Result<()> {
     let devices = list_devices(client).await?;
     if devices.is_empty() {
         display::print_status("No devices registered.");
@@ -3260,7 +3260,7 @@ async fn cmd_devices(client: &node_service::Client) -> anyhow::Result<()> {
     Ok(())
 }
 
-async fn cmd_register_device(
+pub(crate) async fn cmd_register_device(
     client: &node_service::Client,
     name: &str,
 ) -> anyhow::Result<()> {
@@ -3279,7 +3279,7 @@ async fn cmd_register_device(
     Ok(())
 }
 
-async fn cmd_revoke_device(
+pub(crate) async fn cmd_revoke_device(
     client: &node_service::Client,
     id_prefix: &str,
 ) -> anyhow::Result<()> {

crates/quicproquo-client/src/client/rpc.rs

@@ -152,7 +152,7 @@ pub fn set_auth(auth: &mut auth::Builder<'_>) -> anyhow::Result<()> {
         )
     })?;
     auth.set_version(ctx.version);
-    auth.set_access_token(&ctx.access_token);
+    auth.set_access_token(&*ctx.access_token);
     auth.set_device_id(&ctx.device_id);
     Ok(())
 }

crates/quicproquo-client/src/client/session.rs

@@ -9,6 +9,7 @@ use std::sync::Arc;
 use std::time::Instant;
 
 use anyhow::Context;
+use zeroize::Zeroizing;
 
 use quicproquo_core::{DiskKeyStore, GroupMember, HybridKeypair, IdentityKeypair};
 
@@ -25,8 +26,8 @@ pub struct SessionState {
     pub hybrid_kp: Option<HybridKeypair>,
     /// Path to the legacy state file (for backward compat with one-shot commands).
     pub state_path: PathBuf,
-    /// Optional password for the legacy state file.
-    pub password: Option<String>,
+    /// Optional password for the legacy state file. Zeroized on drop. (M9)
+    pub password: Option<Zeroizing<String>>,
     /// SQLite-backed conversation + message store.
     pub conv_store: ConversationStore,
     /// Currently active conversation.
@@ -80,7 +81,7 @@ impl SessionState {
             identity,
             hybrid_kp,
             state_path: state_path.to_path_buf(),
-            password: password.map(String::from),
+            password: password.map(|p| Zeroizing::new(String::from(p))),
             conv_store,
             active_conversation: None,
             members: HashMap::new(),
@@ -183,7 +184,10 @@ impl SessionState {
     fn create_member_from_conv(&self, conv: &Conversation) -> anyhow::Result<GroupMember> {
         let ks_path = self.keystore_path_for(&conv.id);
         let ks = DiskKeyStore::persistent(&ks_path)
-            .unwrap_or_else(|_| DiskKeyStore::ephemeral());
+            .unwrap_or_else(|e| {
+                tracing::warn!(path = %ks_path.display(), error = %e, "DiskKeyStore open failed, falling back to ephemeral");
+                DiskKeyStore::ephemeral()
+            });
 
         let group = conv
             .mls_group_blob

crates/quicproquo-client/src/client/state.rs

@@ -55,7 +55,7 @@ impl StoredState {
             .transpose()?;
 
         Ok(Self {
-            identity_seed: member.identity_seed(),
+            identity_seed: *member.identity_seed(),
             group,
             hybrid_key: hybrid_kp.map(|kp| kp.to_bytes()),
             member_keys: Vec::new(),

crates/quicproquo-client/src/client/token_cache.rs

@@ -64,7 +64,14 @@ pub fn save_cached_session(
 
     let bytes = match password {
         Some(pw) => encrypt_state(pw, contents.as_bytes())?,
-        None => contents.into_bytes(),
+        None => {
+            #[cfg(not(unix))]
+            tracing::warn!(
+                "storing session token as plaintext (no password set); \
+                 file permissions cannot be restricted on this platform"
+            );
+            contents.into_bytes()
+        }
     };
 
     std::fs::write(&path, bytes).with_context(|| format!("write session cache {path:?}"))?;

crates/quicproquo-client/src/client/tui/mod.rs

@@ -644,7 +644,7 @@ async fn tui_loop(
     // Clone session state for the poll task (it needs its own SessionState).
     let poll_session = SessionState::load(
         &session.state_path.clone(),
-        session.password.as_deref(),
+        session.password.as_ref().map(|p| p.as_str()),
     )?;
     let poll_tx = event_tx.clone();
     tokio::task::spawn_local(poll_task(poll_session, client.clone(), poll_tx));

crates/quicproquo-client/src/lib.rs

@@ -17,6 +17,8 @@
 use std::sync::RwLock;
 use std::sync::atomic::{AtomicBool, Ordering};
 
+use zeroize::Zeroizing;
+
 pub mod client;
 
 pub use client::commands::{
@@ -26,14 +28,85 @@ pub use client::commands::{
     cmd_send, cmd_whoami, opaque_login, receive_pending_plaintexts, whoami_json,
 };
 
+pub use client::command_engine::{Command, CommandRegistry, CommandResult};
+#[cfg(feature = "playbook")]
+pub use client::playbook::{Playbook, PlaybookReport, PlaybookRunner};
 pub use client::repl::run_repl;
 pub use client::rpc::{connect_node, connect_node_opt, create_channel, enqueue, fetch_wait, resolve_user};
 
-// Global auth context — RwLock so the REPL can set it after OPAQUE login.
+// ── ClientContext: structured holder for session-scoped auth + TLS config ────
+
+/// Holds the authentication credentials and TLS policy for a client session.
+///
+/// Prefer constructing a `ClientContext` and passing it explicitly where
+/// possible. The global `AUTH_CONTEXT` / `INSECURE_SKIP_VERIFY` statics
+/// delegate to a `ClientContext` under the hood and exist only for backward
+/// compatibility with call-sites that have not yet been migrated.
+pub struct ClientContext {
+    auth: RwLock<Option<ClientAuth>>,
+    insecure_skip_verify: AtomicBool,
+}
+
+impl ClientContext {
+    /// Create a new context with no auth and TLS verification enabled.
+    pub fn new() -> Self {
+        Self {
+            auth: RwLock::new(None),
+            insecure_skip_verify: AtomicBool::new(false),
+        }
+    }
+
+    /// Create a context pre-loaded with auth credentials.
+    pub fn with_auth(auth: ClientAuth) -> Self {
+        Self {
+            auth: RwLock::new(Some(auth)),
+            insecure_skip_verify: AtomicBool::new(false),
+        }
+    }
+
+    /// Set (or replace) the auth credentials.
+    pub fn set_auth(&self, ctx: ClientAuth) {
+        let mut guard = self.auth.write().expect("ClientContext auth lock poisoned");
+        *guard = Some(ctx);
+    }
+
+    /// Read the current auth snapshot (cloned).
+    pub fn get_auth(&self) -> Option<ClientAuth> {
+        let guard = self.auth.read().expect("ClientContext auth lock poisoned");
+        guard.clone()
+    }
+
+    /// Returns true if auth credentials have been set.
+    pub fn is_authenticated(&self) -> bool {
+        let guard = self.auth.read().expect("ClientContext auth lock poisoned");
+        guard.is_some()
+    }
+
+    /// Enable or disable insecure TLS mode.
+    pub fn set_insecure_skip_verify(&self, enabled: bool) {
+        self.insecure_skip_verify.store(enabled, Ordering::Relaxed);
+    }
+
+    /// Read the current insecure-skip-verify flag.
+    pub fn insecure_skip_verify(&self) -> bool {
+        self.insecure_skip_verify.load(Ordering::Relaxed)
+    }
+}
+
+impl Default for ClientContext {
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+// ── Global statics (thin wrappers, kept for backward compat) ─────────────────
+
+/// Global auth context — delegates to a process-wide `ClientContext`.
+/// Prefer passing `&ClientContext` explicitly in new code.
 pub(crate) static AUTH_CONTEXT: RwLock<Option<ClientAuth>> = RwLock::new(None);
 
 /// When `true`, [`connect_node`] skips TLS certificate verification.
-/// Set via [`set_insecure_skip_verify`]; read by the RPC layer.
+/// Prefer `ClientContext::set_insecure_skip_verify` in new code.
 pub(crate) static INSECURE_SKIP_VERIFY: AtomicBool = AtomicBool::new(false);
 
 /// Enable or disable insecure (no-verify) TLS mode globally.
@@ -47,7 +120,8 @@ pub fn set_insecure_skip_verify(enabled: bool) {
 #[derive(Clone, Debug)]
 pub struct ClientAuth {
     pub(crate) version: u16,
-    pub(crate) access_token: Vec<u8>,
+    /// Bearer or OPAQUE session token. Zeroized on drop. (M8)
+    pub(crate) access_token: Zeroizing<Vec<u8>>,
     pub(crate) device_id: Vec<u8>,
 }
 
@@ -58,7 +132,7 @@ impl ClientAuth {
         let device = device_id.unwrap_or_default().into_bytes();
         Self {
             version: 1,
-            access_token: token,
+            access_token: Zeroizing::new(token),
             device_id: device,
         }
     }
@@ -68,7 +142,7 @@ impl ClientAuth {
         let device = device_id.unwrap_or_default().into_bytes();
         Self {
             version: 1,
-            access_token: raw_token,
+            access_token: Zeroizing::new(raw_token),
             device_id: device,
         }
     }

crates/quicproquo-client/src/main.rs

@@ -393,6 +393,34 @@ enum Command {
         #[arg(long)]
         input: PathBuf,
     },
+
+    /// Execute a YAML playbook (scripted command sequence) and exit.
+    /// Requires `--features playbook`.
+    #[cfg(feature = "playbook")]
+    Run {
+        /// Path to the YAML playbook file.
+        playbook: PathBuf,
+
+        /// State file path (identity + MLS state).
+        #[arg(long, default_value = "qpq-state.bin", env = "QPQ_STATE")]
+        state: PathBuf,
+
+        /// Server address (host:port).
+        #[arg(long, default_value = "127.0.0.1:7000", env = "QPQ_SERVER")]
+        server: String,
+
+        /// OPAQUE username for automatic login.
+        #[arg(long, env = "QPQ_USERNAME")]
+        username: Option<String>,
+
+        /// OPAQUE password.
+        #[arg(long, env = "QPQ_PASSWORD")]
+        password: Option<String>,
+
+        /// Override playbook variables: KEY=VALUE (repeatable).
+        #[arg(long = "var", short = 'V')]
+        vars: Vec<String>,
+    },
 }
 
 // ── Helpers ───────────────────────────────────────────────────────────────────
@@ -410,6 +438,77 @@ fn derive_state_path(state: PathBuf, username: Option<&str>) -> PathBuf {
     state
 }
 
+// ── Playbook execution ───────────────────────────────────────────────────────
+
+#[cfg(feature = "playbook")]
+async fn run_playbook(
+    playbook_path: &Path,
+    state: &Path,
+    server: &str,
+    ca_cert: &Path,
+    server_name: &str,
+    state_pw: Option<&str>,
+    username: Option<&str>,
+    password: Option<&str>,
+    access_token: &str,
+    device_id: Option<&str>,
+    extra_vars: &[String],
+) -> anyhow::Result<()> {
+    use quicproquo_client::PlaybookRunner;
+
+    let insecure = std::env::var("QPQ_DANGER_ACCEPT_INVALID_CERTS").is_ok();
+
+    // Connect to server.
+    let client =
+        quicproquo_client::connect_node_opt(server, ca_cert, server_name, insecure)
+            .await
+            .context("connect to server")?;
+
+    // Build session state.
+    let mut session = quicproquo_client::client::session::SessionState::load(state, state_pw)
+        .context("load session state")?;
+
+    // If username/password provided, do OPAQUE login.
+    if let (Some(uname), Some(pw)) = (username, password) {
+        if let Err(e) =
+            quicproquo_client::opaque_login(&client, uname, pw, &session.identity.public_key_bytes()).await
+        {
+            eprintln!("OPAQUE login failed: {e:#}");
+        }
+    } else if !access_token.is_empty() {
+        let auth = ClientAuth::from_parts(access_token.to_string(), device_id.map(String::from));
+        init_auth(auth);
+    }
+
+    // Load playbook.
+    let mut runner = PlaybookRunner::from_file(playbook_path)
+        .with_context(|| format!("load playbook: {}", playbook_path.display()))?;
+
+    // Inject extra variables from --var KEY=VALUE flags.
+    for kv in extra_vars {
+        if let Some((k, v)) = kv.split_once('=') {
+            runner.set_var(k, v);
+        } else {
+            eprintln!("warning: ignoring malformed --var '{kv}' (expected KEY=VALUE)");
+        }
+    }
+
+    // Inject connection info as variables.
+    runner.set_var("_server", server);
+    if let Some(u) = username {
+        runner.set_var("_username", u);
+    }
+
+    let report = runner.run(&mut session, &client).await;
+    print!("{report}");
+
+    if report.all_passed() {
+        Ok(())
+    } else {
+        std::process::exit(1);
+    }
+}
+
 // ── Entry point ───────────────────────────────────────────────────────────────
 
 #[tokio::main]
@@ -736,5 +835,32 @@ async fn main() -> anyhow::Result<()> {
             )
         }
         Command::ExportVerify { input } => cmd_export_verify(&input),
+        #[cfg(feature = "playbook")]
+        Command::Run {
+            playbook,
+            state,
+            server,
+            username,
+            password,
+            vars,
+        } => {
+            let state = derive_state_path(state, username.as_deref());
+            let local = tokio::task::LocalSet::new();
+            local
+                .run_until(run_playbook(
+                    &playbook,
+                    &state,
+                    &server,
+                    &args.ca_cert,
+                    &args.server_name,
+                    state_pw,
+                    username.as_deref(),
+                    password.as_deref(),
+                    &args.access_token,
+                    args.device_id.as_deref(),
+                    &vars,
+                ))
+                .await
+        }
     }
 }