AgentBridge
Use one AI to think and another AI to code.
AgentBridge connects AI reasoning environments to local coding agents through MCP (Model Context Protocol), allowing a web-based AI to understand and plan changes while a local coding agent executes them in your workspace.
Let the AI with the best reasoning access think. Let the coding agent you already use execute.
π¨π³ δΈζ Β· π¦ crates.io Β· π GitHub
Why AgentBridge?
AI coding tools increasingly combine two different jobs:
- Reasoning β understanding a codebase, investigating problems, designing solutions, and reviewing changes.
- Execution β editing files, running commands, running tests, and applying changes.
These two jobs do not necessarily need to be performed by the same AI.
You may have a web AI with generous usage and strong reasoning capabilities (such as Claude 3.7 Sonnet, o3-mini, or Gemini 2.5 Pro), while your local coding CLI has a more limited subscription quota.
Without a bridge, the coding agent has to spend its quota on everything:
Understand β Explore β Reason β Plan β Code β Test β Review
AgentBridge separates the workflow:
BRAIN
Web-based AI
Gemini / Claude / ...
β
Reason / Plan
β
MCP
βΌ
βββββββββββββββββββ
β AgentBridge β (Port 8030)
ββββββββββ¬βββββββββ
β
C2C PLAN
β
βΌ
EXECUTOR
Local coding agent
OpenCode
β
Edit / Run / Test
β
βΌ
Local Workspace
The result is simple:
Use the AI that is best at thinking, and the coding agent that is best at doing.
The Core Idea
AgentBridge introduces two explicit roles.
π§ Brain
The Brain is the AI responsible for reasoning.
It can:
- inspect the project and directory structure;
- search the codebase;
- read files;
- understand architecture and investigate bugs;
- create structured implementation plans (C2C PLAN);
- trigger execution via
task_start; - inspect Git diffs and test results;
- review the Executor's work.
The Brain interacts with the workspace through AgentBridge's read-only MCP interface. It does not directly execute arbitrary shell commands or overwrite files.
π οΈ Executor
The Executor is the local coding agent responsible for execution.
It can:
- modify and create files;
- run build and test commands;
- implement the Brain's plan;
- report execution results.
AgentBridge currently features OpenCode as its primary Executor. The architecture is designed so additional coding agents (Claude Code, Aider, Codex) can be supported in the future.
π AgentBridge
AgentBridge connects the two.
It provides:
- Streamable HTTP MCP server;
- safe read-only project inspection;
- structured task delegation (C2C Protocol);
- autonomous task supervisor (
task_start,task_status,task_cancel); - live terminal output streaming (
mode = "stream"); - automatic reasoning token (
<think>) stripping; - Git diff & untracked file capture;
- test status reporting.
How It Works
A typical workflow looks like this:
User
β
βΌ
Brain (Claude / ChatGPT / Gemini)
β
βββ Inspect workspace (workspace_info, search_workspace, read_file)
βββ Understand architecture & formulate PLAN
βββ Call task_start
β
βΌ
AgentBridge (v0.2.3)
β
C2C PLAN
β
βΌ
Executor (OpenCode CLI)
β
βββ Edit files
βββ Run commands
βββ Run tests
β
βΌ
Git Diff / Result
β
βΌ
Brain
β
Review (git_diff / test_status)
β
ββββββ΄βββββ
β β
DONE PLAN AGAIN
This creates an autonomous feedback loop:
PLAN β EXECUTE β REVIEW β DONE
β β
βββ PLAN βββββ
MCP: Giving the Brain Access to Your Workspace
AgentBridge uses the Model Context Protocol (MCP) to expose your local project and task controls to the Brain.
Inspection Tools (Read-Only & Safe)
| Tool | Description |
|---|---|
workspace_info |
Inspect workspace path, project types (Rust, Node, Python, Go), and Git repository state |
list_directory |
Traversal-safe structured directory listing |
read_file |
Read UTF-8 files (size-capped, binaries & secrets denied) |
search_workspace |
High-speed keyword search with smart ignores (node_modules, target, .git) |
git_status |
Inspect branch, changed, staged, and untracked files |
git_diff |
Working tree or staged diff (automatically formats newly-created untracked files) |
test_status |
Read the latest recorded test execution result |
execution_summary |
Read structured summary of the latest iteration |
Execution & Control Tools (Autonomous)
| Tool | Description |
|---|---|
task_start |
Spawns local OpenCode with a validated C2cPlan |
task_status |
Polls task lifecycle: running | success | failed | cancelled |
task_cancel |
Terminates the running executor process tree safely |
C2C: Brain-to-Executor Communication
AgentBridge standardizes agent communication using lightweight C2C (Context-to-Context) messages:
[C2C]
STATE: PLAN
TASK_ID: c2c_20260830_001
ITERATION: 1
GOAL:
Add URL inspection support to the GSC client.
ACTIONS:
1. Inspect the existing GSC client.
2. Add URL inspection support.
3. Add tests for indexed and non-indexed URLs.
TESTS:
cargo test
SUCCESS_CRITERIA:
Tests pass and the API correctly reports indexed / non-indexed.
The source code remains in the local workspace. Only the structured task contract crosses the boundary, minimizing context token consumption.
Quick Start
1. Install
Install via Cargo:
Verify the installation:
You can also download pre-built binaries from GitHub Releases.
Build from source:
2. Initialize Your Project
Check your environment:
3. Start AgentBridge
By default, AgentBridge listens on:
http://127.0.0.1:8030/mcp
Connecting Your Brain
Option A: Claude Desktop (Zero-API, 100% Free)
Open %APPDATA%\Claude\claude_desktop_config.json (Windows) or ~/Library/Application Support/Claude/claude_desktop_config.json (macOS):
Restart Claude Desktop. The π¨ icon will appear with all AgentBridge tools loaded.
Option B: Remote Web AI via Cloudflare Tunnel (Gemini / ChatGPT)
In .agentbridge.toml, set allow_any_host = true, then start:
In another terminal, expose port 8030:
Point any remote MCP-compatible client to https://<your-tunnel-id>.trycloudflare.com/mcp.
Configuration (.agentbridge.toml)
agentbridge init generates a project-level configuration:
= "D:\\Project\\MyProject"
= "127.0.0.1"
= 8030
= false # Set true when routing via Cloudflare Tunnel
= "optional_bearer_token" # Recommended for public tunnels
[]
= "opencode"
= "opencode" # On Windows with global npm, use "opencode.cmd"
= "stream" # "stream" (live terminal output) or "silent" (quiet background)
[]
= 1048576 # 1MB
= true # Denies .env, *.pem, *.key, id_rsa
= 65536 # Truncates diffs over 64KB
π‘ Windows Tip: If OpenCode is installed globally via npm, set
command = "opencode.cmd"(or the absolute path) to ensure Windows invokes the batch wrapper rather than the POSIX shell script (preventingos error 193).
CLI Reference
# Initialize project workspace
# Start MCP server (loads settings from .agentbridge.toml)
# Inspect workspace, git, and executor status
# Diagnose environment, git, and OpenCode installation
# Manually start a task from CLI and execute synchronously
# Cancel running executor task
Security
AgentBridge is built with defensive defaults:
- Explicit Read-Only View: The remote Brain cannot execute arbitrary shell commands or overwrite files.
- Deny-by-Default File Access: Restricts path traversal (
../) and sensitive file patterns (.env,credentials,id_rsa,*.pem). - Process Sandboxing: The Executor is strictly bounded to the workspace directory.
- Authentication: Supports Bearer Token authorization (
auth_token) for public deployments.
License
MIT License Β© AgentBridge Contributors