opencode subagents MCP server

opencode-subagent-mcp

Run Claude Code subagents on cheaper opencode models — for example opencode-go/deepseek-v4.1-flash (DeepSeek) from an opencode Go subscription — while Claude Code itself keeps talking to Anthropic directly. Delegate searches, refactors, bug fixes, tests and research to a model that costs a fraction of Opus or Sonnet, and keep the tools you already use: background agents, resume via send_message, worktree isolation, .claude/agents definitions, permission prompts and structured output.

It is a stdio MCP server. Your main Claude Code session is not proxied or routed anywhere; the server only runs the subagents you delegate to it, on a private opencode serve instance it starts itself.

Install

Requires Node 22+, git, and the opencode CLI logged in to the providers you want (opencode auth login).

As a Claude Code plugin (also adds a skill that tells Claude when to delegate to opencode):

claude plugin marketplace add sebstaq/opencode-subagent-mcp
claude plugin install opencode-subagent-mcp@sebstaq-opencode

Or as a plain MCP server:

claude mcp add -s user opencode -- npx -y opencode-subagent-mcp@0.1.2

What it runs and sends

password, and stops it when Claude Code exits. The password is generated for each run and only used between this server and that local process. The process inherits your environment so opencode can use the provider logins and API keys you already configured for it; this server never reads, stores or sends those credentials itself.

• It starts a private opencode serve process on a random localhost port with a random

model provider you choose through opencode (by default opencode Go), under that provider's data retention terms. opencode keeps session history in its local database on your machine. Nothing else is sent anywhere; the server has no telemetry and makes no other network calls.

• The prompts you delegate, and the files and command output the subagent reads, go to the

.claude/settings.local.json, and .claude/agents/*.md (user and project) to mirror your permission rules and agent definitions, and ~/.config/opencode-subagent-mcp/config.json if present.

• It reads ~/.claude/settings.json, the project's .claude/settings.json and

.claude/worktrees/ and removes them when they have no changes.

• With isolation: "worktree" it creates git worktrees under the project's

This is an independent project, not affiliated with Anthropic or the opencode team.

Tools

agent parameters: description, prompt, subagenttype, model, isolation: "worktree", permissionmode, tools, disallowedtools, maxturns, effort, outputschema, runin_background, cwd.

Parity with native subagents

Shortened. The full README is on GitHub.