oh-my-opencode/src/mcp/AGENTS.md

src/mcp/ — 5 Built-in MCPs

Generated: 2026-05-18

OVERVIEW

Tier 1 of the three-tier MCP system. Built-ins are created by createBuiltinMcps(disabledMcps, config, options) and now include both remote MCPs and local stdio MCPs.

BUILT-IN MCPs

Name	Type	Endpoint / Command	Env Vars	Tools
websearch	remote	mcp.exa.ai (default) or mcp.tavily.com	EXA_API_KEY (optional), TAVILY_API_KEY (if tavily)	Web search
context7	remote	mcp.context7.com/mcp	CONTEXT7_API_KEY (optional)	Library documentation
grep_app	remote	mcp.grep.app	None	GitHub code search
lsp	local (stdio, node/bun)	node packages/lsp-tools-mcp/dist/cli.js mcp or bun packages/lsp-tools-mcp/src/cli.ts mcp	LSP_TOOLS_MCP_PROJECT_CONFIG=.opencode/lsp.json	status, diagnostics, goto definition, references, symbols, prepare_rename, rename
ast_grep	local (stdio, node/bun)	node packages/ast-grep-mcp/dist/cli.js mcp or bun packages/ast-grep-mcp/src/cli.ts mcp	OMO_AST_GREP_WORKSPACE=<project>	search, replace

SUBMODULE ARCHITECTURE

• The local lsp MCP is a git submodule at packages/lsp-tools-mcp/.
• Upstream project: https://github.com/code-yeongyu/lsp-tools-mcp
• OMO resolves the CLI path dynamically in src/mcp/lsp.ts so both src/ and dist/ runtime layouts work.
• lsp and ast_grep are registered whenever they are not listed in disabled_mcps, even if their CLI artifacts have not been built yet. Source checkouts fall back to the Bun source CLI; packaged builds prefer the Node dist CLI.

THREE-TIER SYSTEM

Tier	Source	Mechanism
1. Built-in	src/mcp/	3 remote HTTP MCPs + 2 local stdio MCPs (lsp, ast_grep) via createBuiltinMcps()
2. Claude Code	.mcp.json	${VAR} expansion via claude-code-mcp-loader
3. Skill-embedded	SKILL.md YAML	Managed by SkillMcpManager (stdio + HTTP)

FILES

File	Purpose
index.ts	createBuiltinMcps() registry for built-in MCPs
types.ts	McpNameSchema: "websearch" | "context7" | "grep_app" | "lsp" | "ast_grep"
websearch.ts	Exa/Tavily provider with config
context7.ts	Context7 with optional auth header
grep-app.ts	Grep.app (no auth)
lsp.ts	Local stdio MCP config for packaged lsp-tools-mcp
ast-grep.ts	Local stdio MCP config for packaged ast-grep-mcp