Hmbown · aboimpinto · May 18, 2026 · May 19, 2026 · May 24, 2026 · May 24, 2026
diff --git a/config.example.toml b/config.example.toml
@@ -576,8 +576,61 @@ default_text_model = "deepseek-ai/deepseek-v4-pro"
 # [runtime_api]
 # cors_origins = ["http://localhost:5173", "http://127.0.0.1:5173"]
 
+# ─────────────────────────────────────────────────────────────────────────────────
+# Tool Overrides & Plugins ([tools])
+# ─────────────────────────────────────────────────────────────────────────────────
+# The `[tools]` table lets you replace any built-in tool with a custom
+# implementation (script or command) or disable it entirely — without
+# forking or recompiling the binary.
+#
+# Plugin scripts dropped in the plugin directory are auto-discovered and
+# registered as model-visible tools alongside the built-in ones.
+#
+# Scripts receive the tool's JSON input on **stdin** and must return a
+# JSON `ToolResult` (`{"content": "...", "success": true}`) on **stdout**.
+#
+# [tools]
+# # Custom plugin directory (defaults to `~/.deepseek/tools/`)
+# plugin_dir = "~/.deepseek/tools"
+#
+# [tools.overrides]
+# # Disable a tool entirely — removes it from the model-visible catalog.
+# "code_execution" = { type = "disabled" }
+#
+# # Replace a tool with a script. Relative paths resolve against plugin_dir.
+# "exec_shell" = { type = "script", path = "audit-exec-shell.sh" }
+#
+# # Replace a tool with a command (binary on PATH or absolute path).
+# "read_file" = { type = "command", command = "bat", args = ["--paging=never"] }
+#
+# # Scripts can also accept static arguments before the JSON input:
+# "fetch_url" = { type = "script", path = "cached-fetch.sh", args = ["--ttl", "300"] }
+
+# ──────────── Enterprise example: audit-logging exec_shell wrapper ──────────────
+# Drop `audit-exec-shell.sh` in `~/.deepseek/tools/` and enable with:
+#
+# [tools.overrides]
+# "exec_shell" = { type = "script", path = "audit-exec-shell.sh" }
+#
+# The wrapper logs every command to `~/.deepseek/audit/exec_shell.log` before
+# executing it, then runs the real `exec_shell` tool logic via stdin/stdout
+# passthrough. No code changes, no fork, no recompile.
+#
+# ```sh
+# #!/usr/bin/env sh
+# # name: exec_shell
+# # description: Audit-logging wrapper for exec_shell
+# # approval: required
+# LOGDIR="${HOME}/.deepseek/audit"
+# mkdir -p "$LOGDIR"
+# LOGFILE="$LOGDIR/exec_shell.log"
+# input=$(cat)
+# echo "[$(date -Iseconds)] $input" >> "$LOGFILE"
+# echo "$input" | exec /bin/sh -s
+# ```
+
 # ─────────────────────────────────────────────────────────────────────────────────
 # Requirements (admin constraints) example file
 # ─────────────────────────────────────────────────────────────────────────────────
 # allowed_approval_policies = ["on-request", "untrusted", "never"]
-# allowed_sandbox_modes = ["read-only", "workspace-write"]
+# allowed_sandbox_modes = ["read-only", "workspace-write"]
diff --git a/crates/tui/src/commands/share.rs b/crates/tui/src/commands/share.rs
@@ -12,6 +12,7 @@ use std::io::Write;
 use std::path::Path;
 
 use super::CommandResult;
+use crate::dependencies::ExternalTool;
 use crate::tui::app::{App, AppAction};
 
 /// Share the current session as a web URL.
@@ -101,7 +102,7 @@ fn render_session_html(history_json: &str, model: &str, mode: &str) -> String {
 <head>
 <meta charset="UTF-8">
 <meta name="viewport" content="width=device-width, initial-scale=1.0">
-<title>codewhale Session Export</title>
+<title>DeepSeek TUI Session Export</title>
 <style>
   body {{
     font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
@@ -119,14 +120,14 @@ fn render_session_html(history_json: &str, model: &str, mode: &str) -> String {
 </style>
 </head>
 <body>
-<h1>codewhale Session</h1>
+<h1>DeepSeek TUI Session</h1>
 <div class="meta">
   <strong>Model:</strong> {escaped_model} · <strong>Mode:</strong> {escaped_mode}<br>
   <strong>Exported:</strong> {timestamp}
 </div>
 <pre>{escaped_body}</pre>
 <div class="footer">
-  Generated by codewhale · https://github.com/Hmbown/CodeWhale
+  Generated by DeepSeek TUI · https://github.com/Hmbown/DeepSeek-TUI
 </div>
 </body>
 </html>"#,
@@ -145,7 +146,7 @@ fn html_escape(s: &str) -> String {
 /// Write HTML to a secure temp file and keep it alive for upload.
 fn write_temp_html(html: &str) -> Result<tempfile::NamedTempFile, String> {
     let mut tmp = tempfile::Builder::new()
-        .prefix("codewhale-share-")
+        .prefix("deepseek-share-")
         .suffix(".html")
         .tempfile()
         .map_err(|e| format!("{e}"))?;
@@ -155,16 +156,17 @@ fn write_temp_html(html: &str) -> Result<tempfile::NamedTempFile, String> {
 
 /// Upload a file as a GitHub Gist using the `gh` CLI.
 async fn upload_gist(path: &Path) -> Result<String, String> {
-    let output = tokio::process::Command::new("gh")
+    let output = crate::dependencies::Gh::tokio_command()
+        .ok_or_else(|| "gh not found on PATH".to_string())?
         .args([
             "gist",
             "create",
             "--public",
-            &path.to_string_lossy(),
+            &path.to_string_lossy().to_string(),
             "--filename",
             "session-export.html",
             "--desc",
-            "codewhale Session Export",
+            "DeepSeek TUI Session Export",
         ])
         .output()
         .await
@@ -194,7 +196,7 @@ mod tests {
         assert!(html.contains("deepseek-v4-pro"));
         assert!(html.contains("agent"));
         assert!(html.contains("[{}]"));
-        assert!(html.contains("codewhale"));
+        assert!(html.contains("DeepSeek TUI"));
     }
 
     #[test]
@@ -219,6 +221,6 @@ mod tests {
         assert!(html.contains("plan"));
         assert!(html.contains("test data"));
         assert!(html.contains("Exported:"));
-        assert!(html.contains("https://github.com/Hmbown/CodeWhale"));
+        assert!(html.contains("https://github.com/Hmbown/DeepSeek-TUI"));
     }
 }
diff --git a/crates/tui/src/config.rs b/crates/tui/src/config.rs
@@ -1039,6 +1039,59 @@ pub struct Config {
     /// Vision model configuration for the `image_analyze` tool.
     #[serde(default)]
     pub vision_model: Option<VisionModelConfig>,
+
+    /// Tool override and plugin configuration (`[tools]` table in config.toml).
+    /// When absent, all built-in tools remain as-is and no plugin directory
+    /// is scanned.
+    #[serde(default)]
+    pub tools: Option<ToolsConfig>,
+}
+
+/// Runtime tool override configuration loaded from `[tools]` in config.toml.
+///
+/// Users can replace any built-in tool with a script or external command,
+/// or disable a tool entirely — without forking or recompiling.
+#[derive(Debug, Clone, Default, Deserialize)]
+#[serde(default)]
+pub struct ToolsConfig {
+    /// Optional directory to scan for plugin tool scripts. Scripts with a
+    /// frontmatter header (`# name:`, `# description:`, `# schema:`) are
+    /// auto-discovered and registered as tools.
+    ///
+    /// Defaults to `~/.deepseek/tools/` when `None`.
+    pub plugin_dir: Option<String>,
+
+    /// Per-tool overrides keyed by built-in tool name.
+    /// Each override replaces or disables the named tool.
+    #[serde(default)]
+    pub overrides: Option<HashMap<String, ToolOverride>>,
+}
+
+/// How a user wants to replace or disable a built-in tool.
+#[derive(Debug, Clone, Deserialize)]
+#[serde(tag = "type", rename_all = "snake_case")]
+pub enum ToolOverride {
+    /// Run a local script file. The script receives the tool's JSON input
+    /// on stdin and must return a JSON `ToolResult` on stdout.
+    Script {
+        /// Path to the script (absolute, or relative to `~/.deepseek/tools/`).
+        path: String,
+        /// Optional static arguments prepended before the tool's JSON input.
+        #[serde(default)]
+        args: Option<Vec<String>>,
+    },
+    /// Run an external command. The command receives the tool's JSON input
+    /// on stdin and must return a JSON `ToolResult` on stdout.
+    Command {
+        /// The command to run (binary name or absolute path).
+        command: String,
+        /// Optional static arguments prepended before the tool's JSON input.
+        #[serde(default)]
+        args: Option<Vec<String>>,
+    },
+    /// Completely disable a built-in tool. The tool will not appear in the
+    /// model-visible catalog and cannot be called.
+    Disabled,
 }
 
 /// Vision model configuration for the `image_analyze` tool.
@@ -2971,6 +3024,7 @@ fn merge_config(base: Config, override_cfg: Config) -> Config {
         strict_tool_mode: override_cfg.strict_tool_mode.or(base.strict_tool_mode),
         runtime_api: override_cfg.runtime_api.or(base.runtime_api),
         workshop: override_cfg.workshop.or(base.workshop),
+        tools: override_cfg.tools.or(base.tools),
     }
 }
 

diff --git a/crates/tui/src/core/engine.rs b/crates/tui/src/core/engine.rs
@@ -171,6 +171,11 @@ pub struct EngineConfig {
     /// once at engine construction, then threaded onto every
     /// `SubAgentRuntime` the engine builds (#1806, #1808).
     pub subagent_api_timeout: Duration,
+
+    /// Tool override and plugin configuration (`[tools]` table in config.toml).
+    /// Applied to the per-turn tool registry after built-in tools are registered.
+    /// When `None`, no overrides or plugin loading occurs.
+    pub tools: Option<crate::config::ToolsConfig>,
 }
 
 impl Default for EngineConfig {
@@ -214,6 +219,7 @@ impl Default for EngineConfig {
             subagent_api_timeout: Duration::from_secs(
                 crate::config::DEFAULT_SUBAGENT_API_TIMEOUT_SECS,
             ),
+            tools: None,
         }
     }
 }
@@ -298,7 +304,7 @@ pub struct Engine {
     /// can fan completion events back into the engine.
     tx_subagent_completion: mpsc::UnboundedSender<SubAgentCompletion>,
     /// Receiver paired with `tx_subagent_completion`. Drained at the
-    /// turn-loop's empty-tool_uses branch to surface `<codewhale:subagent.done>`
+    /// turn-loop's empty-tool_uses branch to surface `<deepseek:subagent.done>`
     /// sentinels into the parent's transcript before deciding to end the turn.
     pub(super) rx_subagent_completion: mpsc::UnboundedReceiver<SubAgentCompletion>,
     cancel_token: CancellationToken,
@@ -1060,7 +1066,7 @@ impl Engine {
             None
         };
 
-        let tool_registry = match mode {
+        let mut tool_registry = match mode {
             AppMode::Agent | AppMode::Yolo => {
                 if self.config.features.enabled(Feature::Subagents) {
                     let runtime = if let Some(client) = self.deepseek_client.clone() {
@@ -1108,13 +1114,83 @@ impl Engine {
             _ => Some(builder.build(tool_context)),
         };
 
+        // Track names added by plugin loading so we never defer them.
+        let mut plugin_tool_names: std::collections::HashSet<String> =
+            std::collections::HashSet::new();
+
+        // Load plugin tools from the user's tools directory and apply any
+        // config.toml overrides. Plugin scripts are auto-discovered and
+        // registered without requiring a `[tools]` config section —
+        // the default `~/.deepseek/tools/` directory is always checked.
+        if let Some(ref mut tool_registry) = tool_registry {
+            // Snapshot built-in tool names before any modifications.
+            let names_before: std::collections::HashSet<String> = tool_registry
+                .names()
+                .into_iter()
+                .map(|s| s.to_string())
+                .collect();
+
+            // Resolve the plugin directory. Defaults to `~/.deepseek/tools/`.
+            let default_dir = {
+                let home = dirs::home_dir()
+                    .map(|h| h.join(".deepseek").join("tools"))
+                    .unwrap_or_else(|| PathBuf::from(".deepseek/tools"));
+                home
+            };
+            let plugin_dir = if let Some(ref tools_config) = self.config.tools
+                && let Some(ref custom_dir) = tools_config.plugin_dir
+            {
+                let p = PathBuf::from(shellexpand::tilde(custom_dir).as_ref());
+                if !p.exists() {
+                    tracing::warn!(
+                        "Configured plugin directory {} does not exist, falling back to default",
+                        p.display()
+                    );
+                    default_dir
+                } else {
+                    p
+                }
+            } else {
+                default_dir
+            };
+
+            // Apply per-tool overrides from config.toml (disable / replace).
+            if let Some(ref tools_config) = self.config.tools
+                && let Some(ref overrides) = tools_config.overrides
+            {
+                tool_registry.apply_overrides(overrides, &plugin_dir);
+            }
+
+            // Load auto-discovered plugin scripts from the tools directory.
+            tool_registry.load_plugins(&plugin_dir);
+
+            // Diff: any tool name that didn't exist before overrides/plugins
+            // is a user-registered tool. These should never be deferred.
+            let names_after: std::collections::HashSet<String> = tool_registry
+                .names()
+                .into_iter()
+                .map(|s| s.to_string())
+                .collect();
+            plugin_tool_names = &names_after - &names_before;
+        }
+
         let mcp_tools = if self.config.features.enabled(Feature::Mcp) {
             self.mcp_tools().await
         } else {
             Vec::new()
         };
+
         let tools = tool_registry.as_ref().map(|registry| {
-            build_model_tool_catalog(registry.to_api_tools_with_cache(true), mcp_tools, mode)
+            let mut catalog =
+                build_model_tool_catalog(registry.to_api_tools_with_cache(true), mcp_tools, mode);
+            // Ensure plugin/override tools are NOT deferred — they should be
+            // immediately visible since the user explicitly opted into them.
+            for tool in &mut catalog {
+                if plugin_tool_names.contains(&tool.name) {
+                    tool.defer_loading = Some(false);
+                }
+            }
+            catalog
         });
 
         // Main turn loop
@@ -1364,7 +1440,7 @@ impl Engine {
                 "Emergency compaction complete: {before_count} → {after_count} messages ({removed} removed), ~{before_tokens} → ~{after_tokens} tokens"
             );
             if retries_used > 0 {
-                details.push_str(&format!(" ({retries_used} retries)"));
+                details.push_str(&format!(" ({} retries)", retries_used));
             }
             if trimmed > 0 {
                 details.push_str(&format!(", trimmed {trimmed} oldest"));
@@ -1383,7 +1459,8 @@ impl Engine {
 
         let message = format!(
             "Emergency context compaction failed to reduce request below model limit \
-             (estimate ~{after_tokens} tokens, budget ~{target_budget})."
+             (estimate ~{} tokens, budget ~{}).",
+            after_tokens, target_budget
         );
         self.emit_compaction_failed(id, true, message.clone()).await;
         let _ = self.tx_event.send(Event::status(message)).await;