gemini-cli/packages/core/src/tools/tool-registry.ts

414 lines
12 KiB
TypeScript

/**
* @license
* Copyright 2025 Google LLC
* SPDX-License-Identifier: Apache-2.0
*/
import { FunctionDeclaration } from '@google/genai';
import { AnyDeclarativeTool, Kind, ToolResult, BaseTool } from './tools.js';
import { Config } from '../config/config.js';
import { spawn } from 'node:child_process';
import { StringDecoder } from 'node:string_decoder';
import { discoverMcpTools } from './mcp-client.js';
import { DiscoveredMCPTool } from './mcp-tool.js';
import { parse } from 'shell-quote';
type ToolParams = Record<string, unknown>;
export class DiscoveredTool extends BaseTool<ToolParams, ToolResult> {
constructor(
private readonly config: Config,
name: string,
readonly description: string,
readonly parameterSchema: Record<string, unknown>,
) {
const discoveryCmd = config.getToolDiscoveryCommand()!;
const callCommand = config.getToolCallCommand()!;
description += `
This tool was discovered from the project by executing the command \`${discoveryCmd}\` on project root.
When called, this tool will execute the command \`${callCommand} ${name}\` on project root.
Tool discovery and call commands can be configured in project or user settings.
When called, the tool call command is executed as a subprocess.
On success, tool output is returned as a json string.
Otherwise, the following information is returned:
Stdout: Output on stdout stream. Can be \`(empty)\` or partial.
Stderr: Output on stderr stream. Can be \`(empty)\` or partial.
Error: Error or \`(none)\` if no error was reported for the subprocess.
Exit Code: Exit code or \`(none)\` if terminated by signal.
Signal: Signal number or \`(none)\` if no signal was received.
`;
super(
name,
name,
description,
Kind.Other,
parameterSchema,
false, // isOutputMarkdown
false, // canUpdateOutput
);
}
async execute(params: ToolParams): Promise<ToolResult> {
const callCommand = this.config.getToolCallCommand()!;
const child = spawn(callCommand, [this.name]);
child.stdin.write(JSON.stringify(params));
child.stdin.end();
let stdout = '';
let stderr = '';
let error: Error | null = null;
let code: number | null = null;
let signal: NodeJS.Signals | null = null;
await new Promise<void>((resolve) => {
const onStdout = (data: Buffer) => {
stdout += data?.toString();
};
const onStderr = (data: Buffer) => {
stderr += data?.toString();
};
const onError = (err: Error) => {
error = err;
};
const onClose = (
_code: number | null,
_signal: NodeJS.Signals | null,
) => {
code = _code;
signal = _signal;
cleanup();
resolve();
};
const cleanup = () => {
child.stdout.removeListener('data', onStdout);
child.stderr.removeListener('data', onStderr);
child.removeListener('error', onError);
child.removeListener('close', onClose);
if (child.connected) {
child.disconnect();
}
};
child.stdout.on('data', onStdout);
child.stderr.on('data', onStderr);
child.on('error', onError);
child.on('close', onClose);
});
// if there is any error, non-zero exit code, signal, or stderr, return error details instead of stdout
if (error || code !== 0 || signal || stderr) {
const llmContent = [
`Stdout: ${stdout || '(empty)'}`,
`Stderr: ${stderr || '(empty)'}`,
`Error: ${error ?? '(none)'}`,
`Exit Code: ${code ?? '(none)'}`,
`Signal: ${signal ?? '(none)'}`,
].join('\n');
return {
llmContent,
returnDisplay: llmContent,
};
}
return {
llmContent: stdout,
returnDisplay: stdout,
};
}
}
export class ToolRegistry {
private tools: Map<string, AnyDeclarativeTool> = new Map();
private config: Config;
constructor(config: Config) {
this.config = config;
}
/**
* Registers a tool definition.
* @param tool - The tool object containing schema and execution logic.
*/
registerTool(tool: AnyDeclarativeTool): void {
if (this.tools.has(tool.name)) {
if (tool instanceof DiscoveredMCPTool) {
tool = tool.asFullyQualifiedTool();
} else {
// Decide on behavior: throw error, log warning, or allow overwrite
console.warn(
`Tool with name "${tool.name}" is already registered. Overwriting.`,
);
}
}
this.tools.set(tool.name, tool);
}
private removeDiscoveredTools(): void {
for (const tool of this.tools.values()) {
if (tool instanceof DiscoveredTool || tool instanceof DiscoveredMCPTool) {
this.tools.delete(tool.name);
}
}
}
/**
* Discovers tools from project (if available and configured).
* Can be called multiple times to update discovered tools.
* This will discover tools from the command line and from MCP servers.
*/
async discoverAllTools(): Promise<void> {
// remove any previously discovered tools
this.removeDiscoveredTools();
this.config.getPromptRegistry().clear();
await this.discoverAndRegisterToolsFromCommand();
// discover tools using MCP servers, if configured
await discoverMcpTools(
this.config.getMcpServers() ?? {},
this.config.getMcpServerCommand(),
this,
this.config.getPromptRegistry(),
this.config.getDebugMode(),
this.config.getWorkspaceContext(),
);
}
/**
* Discovers tools from project (if available and configured).
* Can be called multiple times to update discovered tools.
* This will NOT discover tools from the command line, only from MCP servers.
*/
async discoverMcpTools(): Promise<void> {
// remove any previously discovered tools
this.removeDiscoveredTools();
this.config.getPromptRegistry().clear();
// discover tools using MCP servers, if configured
await discoverMcpTools(
this.config.getMcpServers() ?? {},
this.config.getMcpServerCommand(),
this,
this.config.getPromptRegistry(),
this.config.getDebugMode(),
this.config.getWorkspaceContext(),
);
}
/**
* Discover or re-discover tools for a single MCP server.
* @param serverName - The name of the server to discover tools from.
*/
async discoverToolsForServer(serverName: string): Promise<void> {
// Remove any previously discovered tools from this server
for (const [name, tool] of this.tools.entries()) {
if (tool instanceof DiscoveredMCPTool && tool.serverName === serverName) {
this.tools.delete(name);
}
}
this.config.getPromptRegistry().removePromptsByServer(serverName);
const mcpServers = this.config.getMcpServers() ?? {};
const serverConfig = mcpServers[serverName];
if (serverConfig) {
await discoverMcpTools(
{ [serverName]: serverConfig },
undefined,
this,
this.config.getPromptRegistry(),
this.config.getDebugMode(),
this.config.getWorkspaceContext(),
);
}
}
private async discoverAndRegisterToolsFromCommand(): Promise<void> {
const discoveryCmd = this.config.getToolDiscoveryCommand();
if (!discoveryCmd) {
return;
}
try {
const cmdParts = parse(discoveryCmd);
if (cmdParts.length === 0) {
throw new Error(
'Tool discovery command is empty or contains only whitespace.',
);
}
const proc = spawn(cmdParts[0] as string, cmdParts.slice(1) as string[]);
let stdout = '';
const stdoutDecoder = new StringDecoder('utf8');
let stderr = '';
const stderrDecoder = new StringDecoder('utf8');
let sizeLimitExceeded = false;
const MAX_STDOUT_SIZE = 10 * 1024 * 1024; // 10MB limit
const MAX_STDERR_SIZE = 10 * 1024 * 1024; // 10MB limit
let stdoutByteLength = 0;
let stderrByteLength = 0;
proc.stdout.on('data', (data) => {
if (sizeLimitExceeded) return;
if (stdoutByteLength + data.length > MAX_STDOUT_SIZE) {
sizeLimitExceeded = true;
proc.kill();
return;
}
stdoutByteLength += data.length;
stdout += stdoutDecoder.write(data);
});
proc.stderr.on('data', (data) => {
if (sizeLimitExceeded) return;
if (stderrByteLength + data.length > MAX_STDERR_SIZE) {
sizeLimitExceeded = true;
proc.kill();
return;
}
stderrByteLength += data.length;
stderr += stderrDecoder.write(data);
});
await new Promise<void>((resolve, reject) => {
proc.on('error', reject);
proc.on('close', (code) => {
stdout += stdoutDecoder.end();
stderr += stderrDecoder.end();
if (sizeLimitExceeded) {
return reject(
new Error(
`Tool discovery command output exceeded size limit of ${MAX_STDOUT_SIZE} bytes.`,
),
);
}
if (code !== 0) {
console.error(`Command failed with code ${code}`);
console.error(stderr);
return reject(
new Error(`Tool discovery command failed with exit code ${code}`),
);
}
resolve();
});
});
// execute discovery command and extract function declarations (w/ or w/o "tool" wrappers)
const functions: FunctionDeclaration[] = [];
const discoveredItems = JSON.parse(stdout.trim());
if (!discoveredItems || !Array.isArray(discoveredItems)) {
throw new Error(
'Tool discovery command did not return a JSON array of tools.',
);
}
for (const tool of discoveredItems) {
if (tool && typeof tool === 'object') {
if (Array.isArray(tool['function_declarations'])) {
functions.push(...tool['function_declarations']);
} else if (Array.isArray(tool['functionDeclarations'])) {
functions.push(...tool['functionDeclarations']);
} else if (tool['name']) {
functions.push(tool as FunctionDeclaration);
}
}
}
// register each function as a tool
for (const func of functions) {
if (!func.name) {
console.warn('Discovered a tool with no name. Skipping.');
continue;
}
const parameters =
func.parametersJsonSchema &&
typeof func.parametersJsonSchema === 'object' &&
!Array.isArray(func.parametersJsonSchema)
? func.parametersJsonSchema
: {};
this.registerTool(
new DiscoveredTool(
this.config,
func.name,
func.description ?? '',
parameters as Record<string, unknown>,
),
);
}
} catch (e) {
console.error(`Tool discovery command "${discoveryCmd}" failed:`, e);
throw e;
}
}
/**
* Retrieves the list of tool schemas (FunctionDeclaration array).
* Extracts the declarations from the ToolListUnion structure.
* Includes discovered (vs registered) tools if configured.
* @returns An array of FunctionDeclarations.
*/
getFunctionDeclarations(): FunctionDeclaration[] {
const declarations: FunctionDeclaration[] = [];
this.tools.forEach((tool) => {
declarations.push(tool.schema);
});
return declarations;
}
/**
* Retrieves a filtered list of tool schemas based on a list of tool names.
* @param toolNames - An array of tool names to include.
* @returns An array of FunctionDeclarations for the specified tools.
*/
getFunctionDeclarationsFiltered(toolNames: string[]): FunctionDeclaration[] {
const declarations: FunctionDeclaration[] = [];
for (const name of toolNames) {
const tool = this.tools.get(name);
if (tool) {
declarations.push(tool.schema);
}
}
return declarations;
}
/**
* Returns an array of all registered and discovered tool instances.
*/
getAllTools(): AnyDeclarativeTool[] {
return Array.from(this.tools.values()).sort((a, b) =>
a.displayName.localeCompare(b.displayName),
);
}
/**
* Returns an array of tools registered from a specific MCP server.
*/
getToolsByServer(serverName: string): AnyDeclarativeTool[] {
const serverTools: AnyDeclarativeTool[] = [];
for (const tool of this.tools.values()) {
if ((tool as DiscoveredMCPTool)?.serverName === serverName) {
serverTools.push(tool);
}
}
return serverTools.sort((a, b) => a.name.localeCompare(b.name));
}
/**
* Get the definition of a specific tool.
*/
getTool(name: string): AnyDeclarativeTool | undefined {
return this.tools.get(name);
}
}