# Remove Tool Selection Strategy Feature - Implementation Plan

## Overview
Complete removal of the "Tool Selection Strategy" feature (also known as "LLM Tool Router" or "Smart Tool Routing"). This experimental feature used a secondary LLM call to dynamically select which tools to present to the main LLM based on the user's query.

## Current State Analysis
The feature is controlled by `GOOSE_ENABLE_ROUTER` config parameter (default: false). It consists of:
- Core implementation files (4 Rust modules + 1 prompt template)
- Integration points in agent, prompt manager, and server routes
- UI settings section in desktop app
- CLI configuration dialog
- Documentation pages

### Key Discoveries:
- Feature is disabled by default and marked as "experimental/preview"
- Only tested with Claude models
- Has telemetry tracking in posthog
- Snapshot tests in `prompt_manager.rs` use `.with_router_enabled(true)` and will need updating
- `agent.rs` test references `tool_route_manager` but only for context setup, not testing router functionality

## Desired End State
- All Tool Selection Strategy code removed from codebase
- No `GOOSE_ENABLE_ROUTER` config handling (ignored if present in user config)
- No `router__llm_search` tool
- No `/agent/update_router_tool_selector` API endpoint
- No UI settings for tool selection strategy
- No CLI configuration for router strategy
- Documentation removed/updated
- All tests pass, linting passes

## What We're NOT Doing
- Cleaning up existing `GOOSE_ENABLE_ROUTER` entries from user config files (will be ignored)
- Adding deprecation warnings
- Keeping any stub code

## Implementation Approach
Remove in dependency order: core files first, then integration points, then UI/CLI, then documentation. This minimizes compilation errors during the process.

---

## Phase 1: Remove Core Implementation Files

### Overview
Delete the core Rust modules that implement the router functionality.

### Changes Required:

#### 1. Delete core router files
**Files to delete:**
- `crates/goose/src/agents/router_tool_selector.rs`
- `crates/goose/src/agents/router_tools.rs`
- `crates/goose/src/agents/tool_route_manager.rs`
- `crates/goose/src/agents/tool_router_index_manager.rs`
- `crates/goose/src/prompts/router_tool_selector.md`

#### 2. Update module declarations
**File**: `crates/goose/src/agents/mod.rs`
**Changes**: Remove module declarations for deleted files

```rust
// REMOVE these lines:
mod router_tool_selector;
mod router_tools;
mod tool_route_manager;
mod tool_router_index_manager;
```

### Success Criteria:

#### Automated Verification:
- [x] Files deleted
- [x] `cargo build -p goose` compiles (will fail until Phase 2 completes)

**Implementation Note**: Phase 1 will cause compilation errors. Proceed immediately to Phase 2.

---

## Phase 2: Update Agent Integration

### Overview
Remove all router-related code from `agent.rs` and related files.

### Changes Required:

#### 1. Update agent.rs
**File**: `crates/goose/src/agents/agent.rs`
**Changes**:

Remove imports:
```rust
// REMOVE:
use crate::agents::router_tools::ROUTER_LLM_SEARCH_TOOL_NAME;
use crate::agents::tool_route_manager::ToolRouteManager;
use crate::agents::tool_router_index_manager::ToolRouterIndexManager;
```

Remove from Agent struct:
```rust
// REMOVE field:
pub tool_route_manager: Arc<ToolRouteManager>,
```

Remove from Agent::new():
```rust
// REMOVE:
tool_route_manager: Arc::new(ToolRouteManager::new()),
```

Remove method `disable_router_for_recipe`:
```rust
// REMOVE entire method:
pub async fn disable_router_for_recipe(&self) {
    self.tool_route_manager.disable_router_for_recipe().await;
}
```

Remove from `dispatch_tool_call` - the `ROUTER_LLM_SEARCH_TOOL_NAME` branch:
```rust
// REMOVE this else-if branch:
} else if tool_call.name == ROUTER_LLM_SEARCH_TOOL_NAME {
    match self
        .tool_route_manager
        .dispatch_route_search_tool(tool_call.arguments.unwrap_or_default())
        .await
    {
        Ok(tool_result) => tool_result,
        Err(e) => return (request_id, Err(e)),
    }
}
```

Remove from `add_extension` - the router indexing logic:
```rust
// REMOVE this block:
// If LLM tool selection is functional, index the tools
if self.tool_route_manager.is_router_functional().await {
    let selector = self.tool_route_manager.get_router_tool_selector().await;
    if let Some(selector) = selector {
        let selector = Arc::new(selector);
        if let Err(e) = ToolRouterIndexManager::update_extension_tools(
            &selector,
            &self.extension_manager,
            &extension.name(),
            "add",
        )
        .await
        {
            return Err(ExtensionError::SetupError(format!(
                "Failed to index tools for extension {}: {}",
                extension.name(),
                e
            )));
        }
    }
}
```

Remove `list_tools_for_router` method:
```rust
// REMOVE entire method:
pub async fn list_tools_for_router(&self) -> Vec<Tool> {
    ...
}
```

Remove from `remove_extension` - the router de-indexing logic:
```rust
// REMOVE this block:
// If LLM tool selection is functional, remove tools from the index
if self.tool_route_manager.is_router_functional().await {
    let selector = self.tool_route_manager.get_router_tool_selector().await;
    if let Some(selector) = selector {
        ToolRouterIndexManager::update_extension_tools(
            &selector,
            &self.extension_manager,
            name,
            "remove",
        )
        .await?;
    }
}
```

Remove `update_router_tool_selector` method:
```rust
// REMOVE entire method:
pub async fn update_router_tool_selector(
    &self,
    provider: Option<Arc<dyn Provider>>,
    reindex_all: Option<bool>,
) -> Result<()> {
    ...
}
```

Remove from `reply_internal` stream - the `record_tool_requests` call:
```rust
// REMOVE:
self.tool_route_manager
    .record_tool_requests(&requests_to_record)
    .await;
```

#### 2. Update extension.rs (PlatformExtensionContext)
**File**: `crates/goose/src/agents/extension.rs`
**Changes**: Remove `tool_route_manager` field from `PlatformExtensionContext` if present

Search for any references to `tool_route_manager` in this file and remove them.

#### 3. Update extension_manager_extension.rs
**File**: `crates/goose/src/agents/extension_manager_extension.rs`
**Changes**: Remove any references to `tool_route_manager`

### Success Criteria:

#### Automated Verification:
- [x] `cargo build -p goose` compiles (may still fail until Phase 3)

---

## Phase 3: Update Prompt Manager

### Overview
Remove router-related prompt building logic.

### Changes Required:

#### 1. Update prompt_manager.rs
**File**: `crates/goose/src/agents/prompt_manager.rs`
**Changes**:

Remove import:
```rust
// REMOVE:
use crate::agents::router_tools::llm_search_tool_prompt;
```

Remove from `SystemPromptContext`:
```rust
// REMOVE field:
#[serde(skip_serializing_if = "Option::is_none")]
tool_selection_strategy: Option<String>,
```

Remove from `SystemPromptBuilder`:
```rust
// REMOVE field:
router_enabled: bool,
```

Remove `with_router_enabled` method:
```rust
// REMOVE entire method:
pub fn with_router_enabled(mut self, enabled: bool) -> Self {
    self.router_enabled = enabled;
    self
}
```

Update `build` method - remove router_enabled from context:
```rust
// REMOVE from SystemPromptContext construction:
tool_selection_strategy: self.router_enabled.then(llm_search_tool_prompt),
```

Update builder initialization:
```rust
// REMOVE from SystemPromptBuilder initialization:
router_enabled: false,
```

#### 2. Update system.md template
**File**: `crates/goose/src/prompts/system.md`
**Changes**: Remove the `{{tool_selection_strategy}}` placeholder line

```markdown
<!-- REMOVE this line: -->
{{tool_selection_strategy}}
```

#### 3. Update snapshot tests
**File**: `crates/goose/src/agents/prompt_manager.rs` (tests section)
**Changes**: Remove `.with_router_enabled(true)` from tests

In `test_one_extension`:
```rust
// REMOVE:
.with_router_enabled(true)
```

In `test_typical_setup`:
```rust
// REMOVE:
.with_router_enabled(true)
```

#### 4. Update/regenerate snapshots
**Files to update:**
- `crates/goose/src/agents/snapshots/goose__agents__prompt_manager__tests__one_extension.snap`
- `crates/goose/src/agents/snapshots/goose__agents__prompt_manager__tests__typical_setup.snap`

Run `cargo test -p goose prompt_manager` with `INSTA_UPDATE=1` to regenerate snapshots, or manually remove the "LLM Tool Selection Instructions" section from each snapshot.

### Success Criteria:

#### Automated Verification:
- [x] `cargo build -p goose` compiles
- [x] `cargo test -p goose` passes (after snapshot updates)

---

## Phase 4: Update Server Routes

### Overview
Remove the `/agent/update_router_tool_selector` endpoint.

### Changes Required:

#### 1. Update agent.rs routes
**File**: `crates/goose-server/src/routes/agent.rs`
**Changes**:

Remove request struct:
```rust
// REMOVE:
#[derive(Deserialize, utoipa::ToSchema)]
pub struct UpdateRouterToolSelectorRequest {
    session_id: String,
}
```

Remove handler function:
```rust
// REMOVE entire function:
#[utoipa::path(
    post,
    path = "/agent/update_router_tool_selector",
    ...
)]
async fn update_router_tool_selector(
    ...
) -> Result<Json<String>, StatusCode> {
    ...
}
```

Remove route from router:
```rust
// REMOVE from routes() function:
.route(
    "/agent/update_router_tool_selector",
    post(update_router_tool_selector),
)
```

### Success Criteria:

#### Automated Verification:
- [x] `cargo build -p goose-server` compiles
- [x] `cargo test -p goose-server` passes

---

## Phase 5: Update CLI Configuration

### Overview
Remove the router configuration dialog from CLI.

### Changes Required:

#### 1. Update configure.rs
**File**: `crates/goose-cli/src/commands/configure.rs`
**Changes**:

Remove the router strategy menu item from `configure_settings_dialog`:
```rust
// REMOVE this item:
.item(
    "goose_router_strategy",
    "Router Tool Selection Strategy",
    "Experimental: configure a strategy for auto selecting tools to use",
)
```

Remove the match arm:
```rust
// REMOVE:
"goose_router_strategy" => {
    configure_goose_router_strategy_dialog()?;
}
```

Remove the entire `configure_goose_router_strategy_dialog` function:
```rust
// REMOVE entire function:
pub fn configure_goose_router_strategy_dialog() -> anyhow::Result<()> {
    ...
}
```

### Success Criteria:

#### Automated Verification:
- [x] `cargo build -p goose-cli` compiles
- [x] `cargo test -p goose-cli` passes

---

## Phase 6: Update Telemetry ✅ COMPLETE

### Overview
Remove router-related telemetry.

### Changes Required:

#### 1. Update posthog.rs
**File**: `crates/goose/src/posthog.rs`
**Changes**:

Remove the router telemetry:
```rust
// REMOVE this block:
if let Ok(router_enabled) = config.get_param::<bool>("GOOSE_ENABLE_ROUTER") {
    event
        .insert_prop("setting_router_enabled", router_enabled)
        .ok();
}
```

### Success Criteria:

#### Automated Verification:
- [x] `cargo build -p goose` compiles

---

## Phase 7: Update Desktop UI ✅ COMPLETE

### Overview
Remove the Tool Selection Strategy settings section from the desktop app.

### Changes Required:

#### 1. Delete UI component directory
**Directory to delete**: `ui/desktop/src/components/settings/tool_selection_strategy/`

#### 2. Update ChatSettingsSection.tsx
**File**: `ui/desktop/src/components/settings/chat/ChatSettingsSection.tsx`
**Changes**:

Remove import:
```typescript
// REMOVE:
import { ToolSelectionStrategySection } from '../tool_selection_strategy/ToolSelectionStrategySection';
```

Remove the Card containing ToolSelectionStrategySection:
```tsx
{/* REMOVE entire Card: */}
<Card className="pb-2 rounded-lg">
  <CardHeader className="pb-0">
    <CardTitle className="">Tool Selection Strategy (preview)</CardTitle>
    <CardDescription>
      Experimental: configure how Goose selects tools for your requests, useful when there are
      many tools. Only tested with Claude models currently.
    </CardDescription>
  </CardHeader>
  <CardContent className="px-2">
    <ToolSelectionStrategySection />
  </CardContent>
</Card>
```

#### 3. Regenerate OpenAPI types
Run: `just generate-openapi`

This will update `ui/desktop/openapi.json` and `ui/desktop/src/api/types.gen.ts` to remove the `UpdateRouterToolSelectorRequest` type.

### Success Criteria:

#### Automated Verification:
- [x] `cd ui/desktop && npm run lint` passes
- [x] `cd ui/desktop && npm run typecheck` passes
- [x] OpenAPI types regenerated

#### Manual Verification:
- [ ] Desktop app Settings > Chat page loads without errors
- [ ] No "Tool Selection Strategy" section visible

---

## Phase 8: Update Documentation ✅ COMPLETE

### Overview
Remove documentation for the removed feature.

### Changes Required:

#### 1. Delete tool-router.md
**File to delete**: `documentation/docs/guides/managing-tools/tool-router.md`

#### 2. Update managing-tools index
**File**: `documentation/docs/guides/managing-tools/index.md`
**Changes**:

Remove the Tool Selection Strategy card:
```tsx
{/* REMOVE: */}
<Card 
  title="Tool Selection Strategy"
  description="Optimize tool selection with dynamic routing that loads only the tools you need, reducing context overhead and improving performance."
  link="/docs/guides/managing-tools/tool-router"
/>
```

#### 3. Update environment-variables.md
**File**: `documentation/docs/guides/environment-variables.md`
**Changes**:

Remove the `GOOSE_ENABLE_ROUTER` row from the table:
```markdown
<!-- REMOVE this row: -->
| `GOOSE_ENABLE_ROUTER` | Enables [intelligent tool selection strategy](/docs/guides/managing-tools/tool-router) | "true", "false" | "false" |
```

Remove from the example section:
```bash
# REMOVE:
# Enable intelligent tool selection
export GOOSE_ENABLE_ROUTER=true
```

#### 4. Check for other documentation references
Search for any other references to "tool selection", "router", or "GOOSE_ENABLE_ROUTER" in documentation and remove them.

### Success Criteria:

#### Automated Verification:
- [x] No remaining references to GOOSE_ENABLE_ROUTER in documentation

#### Manual Verification:
- [ ] No references to Tool Selection Strategy in docs

---

## Phase 9: Update Tests ✅ COMPLETE (merged into earlier phases)

### Overview
Update any remaining tests that reference the removed functionality.

### Changes Required:

#### 1. Update agent.rs tests
**File**: `crates/goose/tests/agent.rs`
**Changes**:

In `extension_manager_tests::setup_agent_with_extension_manager`, remove the `tool_route_manager` from context setup:
```rust
// REMOVE from PlatformExtensionContext:
tool_route_manager: Some(Arc::downgrade(&agent.tool_route_manager)),
```

#### 2. Update PlatformExtensionContext references
Search for any other test files that set up `PlatformExtensionContext` with `tool_route_manager` and remove that field.

### Success Criteria:

#### Automated Verification:
- [x] `cargo test` passes for all crates
- [x] `./scripts/clippy-lint.sh` passes

---

## Phase 10: Final Cleanup and Verification ✅ COMPLETE

### Overview
Final verification that all changes are complete and correct.

### Changes Required:

#### 1. Search for any remaining references
Run these searches to ensure nothing was missed:
```bash
rg "tool_route" --type rust
rg "router_tool" --type rust
rg "RouterToolSelector" --type rust
rg "ROUTER_LLM_SEARCH" --type rust
rg "llm_search_tool" --type rust
rg "GOOSE_ENABLE_ROUTER" --type rust
rg "tool_selection_strategy" --type rust
rg "ToolSelectionStrategy" --type ts --type tsx
```

#### 2. Run full test suite
```bash
cargo fmt
cargo build
cargo test
./scripts/clippy-lint.sh
```

#### 3. Run UI checks
```bash
cd ui/desktop
npm run lint
npm run build
npm test
```

### Success Criteria:

#### Automated Verification:
- [x] All searches return no results (except in thoughts/research)
- [x] `cargo fmt` - no changes
- [x] `cargo build` - succeeds
- [x] `cargo test` - all tests pass
- [x] `./scripts/clippy-lint.sh` - passes
- [x] UI lint/typecheck - passes

#### Manual Verification:
- [ ] Start goose CLI - works normally
- [ ] Start goose desktop - works normally
- [ ] Settings page loads without errors
- [ ] No console errors related to removed feature

---

## Testing Strategy

### Unit Tests:
- Snapshot tests in `prompt_manager.rs` need regeneration (Phase 3)
- Agent tests need `tool_route_manager` references removed (Phase 9)

### Integration Tests:
- Full `cargo test` after all phases
- Desktop app manual testing after Phase 7

### Regression Testing:
- Ensure normal tool calling still works
- Ensure extension add/remove still works
- Ensure all goose modes (auto, approve, smart_approve, chat) still work

---

## Rollback Plan
If issues are discovered:
1. Git revert the changes
2. The feature was disabled by default, so no user impact from keeping it

---

## Notes
- The research document at `thoughts/research/2025-12-22-llm-tool-selection-strategy.md` should be kept for historical reference
- Users with `GOOSE_ENABLE_ROUTER=true` in their config will simply have the setting ignored