v2.0.0-beta: write tools, pending-changes queue, inference loop, API routes

Phase 2 of v2.0. BooCoder is now a functional write-capable chatbot.

Write-path guard: resolveWritePath() uses resolve() (no realpath — files may
not exist for creates) + prefix-check + secret-file deny list (.env, *.pem,
id_rsa*, etc.). 23 unit tests cover traversal attacks.

Pending-changes service: queueEdit/Create/Delete → applyOne/All →
rejectOne/All → rewindOne. Edit diffs stored as JSON {old, new}. All writes
queue before touching disk; apply re-validates the path guard.

5 write tools: edit_file, create_file, delete_file, apply_pending, rewind.
Registered alongside 25 read-only tools from BooChat (30 total, alpha-sorted).
Write tools use a module-level inference context for sql+sessionId injection.

Inference loop via workspace dependency: apps/coder imports
createInferenceRunner, createBroker, ALL_TOOLS from @boocode/server (dist/).
apps/server gains declaration: true + exports map with typed subpath entries.
No code duplication — one inference engine shared by both apps.

API routes: POST /api/sessions/:id/messages (user msg → inference), POST stop,
GET/POST pending-changes CRUD (5 endpoints), WebSocket session streaming.

Dockerfile updated to build apps/server first (coder depends on its .d.ts).
Health endpoint reports tool count: {"ok":true,"db":true,"tools":30}.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

apps/coder/src/services/tools/adapter.ts

@@ -0,0 +1,30 @@
+/**
+ * Adapts BooCoder write tools (which take ToolContext) into BooChat's ToolDef
+ * interface (which takes `projectRoot, extraRoots?`).
+ *
+ * The adapter reads the module-level inference context at execute time, so the
+ * wrapping happens at boot (static) — no per-inference re-wrap needed.
+ */
+
+import type { ToolDef as ServerToolDef } from '@boocode/server/tools';
+import type { ToolDef, ToolContext } from './types.js';
+import { getInferenceContext } from './inference_context.js';
+
+/**
+ * Wrap a BooCoder write tool (execute takes ToolContext) into a BooChat
+ * ToolDef (execute takes projectRoot + optional extraRoots). The adapter
+ * builds the ToolContext from the module-level inference context at call time.
+ */
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export function adaptWriteTool(tool: ToolDef<any>): ServerToolDef<any> {
+  return {
+    name: tool.name,
+    description: tool.description,
+    inputSchema: tool.inputSchema,
+    jsonSchema: tool.jsonSchema,
+    async execute(input: unknown, projectRoot: string, _extraRoots?: readonly string[]): Promise<unknown> {
+      const ctx: ToolContext = getInferenceContext();
+      return tool.execute(input, projectRoot, ctx);
+    },
+  };
+}

apps/coder/src/services/tools/apply_pending.ts

@@ -0,0 +1,44 @@
+import { z } from 'zod';
+import type { ToolDef, ToolContext } from './types.js';
+import { applyAll } from '../pending_changes.js';
+
+const ApplyPendingInput = z.object({});
+type ApplyPendingInputT = z.infer<typeof ApplyPendingInput>;
+
+export const applyPendingTool: ToolDef<ApplyPendingInputT> = {
+  name: 'apply_pending',
+  description:
+    'Apply all pending changes for the current session to disk. ' +
+    'Each queued create/edit/delete is executed in order.',
+  inputSchema: ApplyPendingInput,
+  jsonSchema: {
+    type: 'function',
+    function: {
+      name: 'apply_pending',
+      description:
+        'Apply all pending changes for the current session to disk. ' +
+        'Each queued create/edit/delete is executed in order.',
+      parameters: {
+        type: 'object',
+        properties: {},
+        required: [],
+      },
+    },
+  },
+  async execute(_input: ApplyPendingInputT, projectRoot: string, context: ToolContext): Promise<unknown> {
+    const results = await applyAll(context.sql, context.sessionId, projectRoot);
+    const succeeded = results.filter((r) => r.success).length;
+    const failed = results.filter((r) => !r.success).length;
+
+    return {
+      total: results.length,
+      succeeded,
+      failed,
+      results,
+      message:
+        results.length === 0
+          ? 'No pending changes to apply.'
+          : `Applied ${succeeded}/${results.length} changes.${failed > 0 ? ` ${failed} failed.` : ''}`,
+    };
+  },
+};

apps/coder/src/services/tools/create_file.ts

@@ -0,0 +1,51 @@
+import { z } from 'zod';
+import type { ToolDef, ToolContext } from './types.js';
+import { queueCreate } from '../pending_changes.js';
+
+const CreateFileInput = z.object({
+  file_path: z.string().min(1),
+  content: z.string(),
+});
+type CreateFileInputT = z.infer<typeof CreateFileInput>;
+
+export const createFileTool: ToolDef<CreateFileInputT> = {
+  name: 'create_file',
+  description:
+    'Queue creation of a new file with the given content. ' +
+    'The change is staged in pending_changes and must be applied explicitly.',
+  inputSchema: CreateFileInput,
+  jsonSchema: {
+    type: 'function',
+    function: {
+      name: 'create_file',
+      description:
+        'Queue creation of a new file with the given content. ' +
+        'The change is staged in pending_changes and must be applied explicitly.',
+      parameters: {
+        type: 'object',
+        properties: {
+          file_path: { type: 'string', description: 'Path for the new file (relative to project root or absolute)' },
+          content: { type: 'string', description: 'Full content of the file to create' },
+        },
+        required: ['file_path', 'content'],
+      },
+    },
+  },
+  async execute(input: CreateFileInputT, projectRoot: string, context: ToolContext): Promise<unknown> {
+    const change = await queueCreate(
+      context.sql,
+      context.sessionId,
+      context.taskId,
+      input.file_path,
+      input.content,
+      projectRoot,
+    );
+    return {
+      status: 'queued',
+      change_id: change.id,
+      file_path: change.file_path,
+      operation: 'create',
+      message: `File creation queued: ${change.file_path}. Use apply_pending to write changes to disk.`,
+    };
+  },
+};

apps/coder/src/services/tools/delete_file.ts

@@ -0,0 +1,48 @@
+import { z } from 'zod';
+import type { ToolDef, ToolContext } from './types.js';
+import { queueDelete } from '../pending_changes.js';
+
+const DeleteFileInput = z.object({
+  file_path: z.string().min(1),
+});
+type DeleteFileInputT = z.infer<typeof DeleteFileInput>;
+
+export const deleteFileTool: ToolDef<DeleteFileInputT> = {
+  name: 'delete_file',
+  description:
+    'Queue deletion of a file. ' +
+    'The change is staged in pending_changes and must be applied explicitly.',
+  inputSchema: DeleteFileInput,
+  jsonSchema: {
+    type: 'function',
+    function: {
+      name: 'delete_file',
+      description:
+        'Queue deletion of a file. ' +
+        'The change is staged in pending_changes and must be applied explicitly.',
+      parameters: {
+        type: 'object',
+        properties: {
+          file_path: { type: 'string', description: 'Path to the file to delete (relative to project root or absolute)' },
+        },
+        required: ['file_path'],
+      },
+    },
+  },
+  async execute(input: DeleteFileInputT, projectRoot: string, context: ToolContext): Promise<unknown> {
+    const change = await queueDelete(
+      context.sql,
+      context.sessionId,
+      context.taskId,
+      input.file_path,
+      projectRoot,
+    );
+    return {
+      status: 'queued',
+      change_id: change.id,
+      file_path: change.file_path,
+      operation: 'delete',
+      message: `File deletion queued: ${change.file_path}. Use apply_pending to write changes to disk.`,
+    };
+  },
+};

apps/coder/src/services/tools/edit_file.ts

@@ -0,0 +1,54 @@
+import { z } from 'zod';
+import type { ToolDef, ToolContext } from './types.js';
+import { queueEdit } from '../pending_changes.js';
+
+const EditFileInput = z.object({
+  file_path: z.string().min(1),
+  old_string: z.string().min(1),
+  new_string: z.string(),
+});
+type EditFileInputT = z.infer<typeof EditFileInput>;
+
+export const editFileTool: ToolDef<EditFileInputT> = {
+  name: 'edit_file',
+  description:
+    'Queue an edit to a file. The edit replaces old_string with new_string. ' +
+    'The change is staged in pending_changes and must be applied explicitly.',
+  inputSchema: EditFileInput,
+  jsonSchema: {
+    type: 'function',
+    function: {
+      name: 'edit_file',
+      description:
+        'Queue an edit to a file. The edit replaces old_string with new_string. ' +
+        'The change is staged in pending_changes and must be applied explicitly.',
+      parameters: {
+        type: 'object',
+        properties: {
+          file_path: { type: 'string', description: 'Path to the file to edit (relative to project root or absolute)' },
+          old_string: { type: 'string', description: 'The exact string to find and replace (must appear in the file)' },
+          new_string: { type: 'string', description: 'The replacement string' },
+        },
+        required: ['file_path', 'old_string', 'new_string'],
+      },
+    },
+  },
+  async execute(input: EditFileInputT, projectRoot: string, context: ToolContext): Promise<unknown> {
+    const change = await queueEdit(
+      context.sql,
+      context.sessionId,
+      context.taskId,
+      input.file_path,
+      input.old_string,
+      input.new_string,
+      projectRoot,
+    );
+    return {
+      status: 'queued',
+      change_id: change.id,
+      file_path: change.file_path,
+      operation: 'edit',
+      message: `Edit queued for ${change.file_path}. Use apply_pending to write changes to disk.`,
+    };
+  },
+};

apps/coder/src/services/tools/index.ts

@@ -0,0 +1,26 @@
+import type { ToolDef } from './types.js';
+import { editFileTool } from './edit_file.js';
+import { createFileTool } from './create_file.js';
+import { deleteFileTool } from './delete_file.js';
+import { applyPendingTool } from './apply_pending.js';
+import { rewindTool } from './rewind.js';
+
+export type { ToolDef, ToolContext, ToolJsonSchema } from './types.js';
+
+// All BooCoder write tools. The inference loop (Phase 2B) will combine these
+// with BooChat's read-only tools to form the full tool set available to agents.
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export const WRITE_TOOLS: readonly ToolDef<any>[] = [
+  applyPendingTool,
+  createFileTool,
+  deleteFileTool,
+  editFileTool,
+  rewindTool,
+];
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export const WRITE_TOOLS_BY_NAME: ReadonlyMap<string, ToolDef<any>> = new Map(
+  WRITE_TOOLS.map((t) => [t.name, t]),
+);
+
+export { editFileTool, createFileTool, deleteFileTool, applyPendingTool, rewindTool };

apps/coder/src/services/tools/inference_context.ts

@@ -0,0 +1,36 @@
+import type { Sql } from '../../db.js';
+
+/**
+ * Module-level inference context for write tools.
+ *
+ * Set via `setInferenceContext()` before each inference run starts.
+ * Write tools read it via `getInferenceContext()` during execute.
+ * Same pattern as BooChat's `loadConfig()` singleton — tools need
+ * ambient state that can't be threaded through the tool-phase execute
+ * signature (which is `execute(input, projectRoot, extraRoots?)`).
+ */
+
+export interface InferenceContext {
+  sql: Sql;
+  sessionId: string;
+  taskId: string | null;
+}
+
+let current: InferenceContext | null = null;
+
+export function setInferenceContext(ctx: InferenceContext): void {
+  current = ctx;
+}
+
+export function clearInferenceContext(): void {
+  current = null;
+}
+
+export function getInferenceContext(): InferenceContext {
+  if (!current) {
+    throw new Error(
+      'Write tool called outside inference context — setInferenceContext() was not called before this run',
+    );
+  }
+  return current;
+}

apps/coder/src/services/tools/rewind.ts

@@ -0,0 +1,71 @@
+import { z } from 'zod';
+import type { ToolDef, ToolContext } from './types.js';
+import { rewindOne } from '../pending_changes.js';
+
+const RewindInput = z.object({
+  change_id: z.string().uuid().optional(),
+  all: z.boolean().optional(),
+});
+type RewindInputT = z.infer<typeof RewindInput>;
+
+export const rewindTool: ToolDef<RewindInputT> = {
+  name: 'rewind',
+  description:
+    'Revert applied changes. Provide change_id to revert a specific change, ' +
+    'or set all=true to revert all applied changes for the session (in reverse order).',
+  inputSchema: RewindInput,
+  jsonSchema: {
+    type: 'function',
+    function: {
+      name: 'rewind',
+      description:
+        'Revert applied changes. Provide change_id to revert a specific change, ' +
+        'or set all=true to revert all applied changes for the session (in reverse order).',
+      parameters: {
+        type: 'object',
+        properties: {
+          change_id: { type: 'string', format: 'uuid', description: 'ID of a specific change to revert' },
+          all: { type: 'boolean', description: 'If true, revert all applied changes for this session' },
+        },
+        required: [],
+      },
+    },
+  },
+  async execute(input: RewindInputT, projectRoot: string, context: ToolContext): Promise<unknown> {
+    if (input.change_id) {
+      const result = await rewindOne(context.sql, input.change_id, projectRoot);
+      return {
+        results: [result],
+        message: result.success
+          ? `Reverted change ${input.change_id} (${result.operation} on ${result.file_path}).`
+          : `Failed to revert: ${result.error}`,
+      };
+    }
+
+    if (input.all) {
+      // Rewind all applied changes for this session in reverse order
+      const applied = await context.sql<{ id: string }[]>`
+        SELECT id FROM pending_changes
+        WHERE session_id = ${context.sessionId} AND status = 'applied'
+        ORDER BY created_at DESC
+      `;
+      const results = [];
+      for (const row of applied) {
+        results.push(await rewindOne(context.sql, row.id, projectRoot));
+      }
+      const succeeded = results.filter((r) => r.success).length;
+      return {
+        total: results.length,
+        succeeded,
+        failed: results.length - succeeded,
+        results,
+        message:
+          results.length === 0
+            ? 'No applied changes to revert.'
+            : `Reverted ${succeeded}/${results.length} changes.`,
+      };
+    }
+
+    return { error: 'Provide either change_id or all=true.' };
+  },
+};

apps/coder/src/services/tools/types.ts

@@ -0,0 +1,32 @@
+import type { z } from 'zod';
+import type { Sql } from '../../db.js';
+
+export interface ToolJsonSchema {
+  type: 'function';
+  function: {
+    name: string;
+    description: string;
+    parameters: Record<string, unknown>;
+  };
+}
+
+/**
+ * Context passed to BooCoder tool execute functions.
+ *
+ * Unlike BooChat's tools (which only need projectRoot), BooCoder's write tools
+ * interact with the database (pending_changes table) and need session/task
+ * context for proper attribution.
+ */
+export interface ToolContext {
+  sql: Sql;
+  sessionId: string;
+  taskId: string | null;
+}
+
+export interface ToolDef<TInput> {
+  name: string;
+  description: string;
+  inputSchema: z.ZodType<TInput>;
+  jsonSchema: ToolJsonSchema;
+  execute(input: TInput, projectRoot: string, context: ToolContext): Promise<unknown>;
+}