OpenRouter Agents MCP Server

Production MCP server for multi-agent AI research. Plan, parallelize, synthesize.

Install

npx @terminals-tech/openrouter-agents --stdio

Claude Code one-liner:

claude mcp add openrouter-agents -- npx @terminals-tech/openrouter-agents --stdio

What's New (v2.0.0)

• MCP SDK 1.27.1 — registerTool/registerPrompt/registerResource APIs, security fixes
• Zod 4 — Upgraded from Zod 3; z.record() syntax, config schema fixes
• Express 5 — Upgraded from Express 4; modern path patterns, req.query handling
• Streamable HTTP — Primary transport (SSE deprecated as legacy fallback)
• Circuit breaker — Model API fault tolerance with configurable thresholds
• Embedding-based model routing — Local vector similarity for model selection (no LLM call)
• Persistent storage — Reports, jobs, knowledge graph persist across sessions by default

macOS/Node 25 Note: A cosmetic libc++abi: mutex lock failed message may appear on shutdown. This is harmless — data is checkpointed before shutdown. Set DB_AUTO_HEAL=true for in-memory mode (no persistence, no message).

Full Changelog | Extensions Guide | MCP Compliance Report

Configuration

Set OPENROUTER_API_KEY in your environment, then configure via .env or .mcp.json:

Variable	Default	Description
OPENROUTER_API_KEY	required	OpenRouter API key
OPENROUTER_API_KEYS	(optional)	Comma-separated OpenRouter keys for rotation
OPENROUTER_KEY_COOLDOWN_MS	5000	Base cooldown per key after failures
SERVER_PORT	3002	HTTP server port
MODE	ALL	AGENT, MANUAL, or ALL
EMBEDDING_ROUTING_ENABLED	true	Enable embedding-based model routing
INDEXER_ENABLED	true	Enable knowledge indexing

Full ENV Reference

.mcp.json example (team-shareable)

{
  "mcpServers": {
    "openrouter-agents": {
      "command": "npx",
      "args": ["@terminals-tech/openrouter-agents", "--stdio"],
      "env": {
        "OPENROUTER_API_KEY": "${OPENROUTER_API_KEY}",
        "INDEXER_ENABLED": "true"
      }
    }
  }
}

Multi-Client Setup

Transport Modes

Transport	Flag	Use Case
STDIO	(default)	MCP clients (Claude, Jan AI, Continue)
HTTP	--http	Web apps, shared server

STDIO is the default transport per MCP spec. Use --http explicitly for HTTP mode.

Client-Specific Setup

Jan AI

1. Enable MCP Servers in Settings → Advanced → Experimental
2. Click + to add server
3. Configure:
   • Name: openrouter-agents
   • Command: npx
   • Arguments: @terminals-tech/openrouter-agents
   • Environment: OPENROUTER_API_KEY=sk-or-...

Note: STDIO is now default - no --stdio flag needed.

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows):

{
  "mcpServers": {
    "openrouter-agents": {
      "command": "npx",
      "args": ["@terminals-tech/openrouter-agents"],
      "env": {
        "OPENROUTER_API_KEY": "sk-or-..."
      }
    }
  }
}

Continue / Zed / Other MCP Clients

Standard MCP config - STDIO is default, no flags needed:

{
  "command": "npx",
  "args": ["@terminals-tech/openrouter-agents"],
  "env": { "OPENROUTER_API_KEY": "..." }
}

Feature Matrix

Feature	All MCP Clients	Claude Code Only
Core Research Tools	✓	✓
Knowledge Base	✓	✓
Session/Graph Tools	✓	✓
Rail Protocol Tools	✓	✓
Slash Commands	-	✓

Models (v2.0.0)

High-Cost Tier

Model	Domains
anthropic/claude-sonnet-4.5	reasoning, technical, general, creative
anthropic/claude-opus-4.6	reasoning, technical, general, creative
openai/gpt-5.2-chat	reasoning, technical, general
openai/gpt-5.3-codex	coding, technical, reasoning
google/gemini-3-pro-preview	reasoning, technical, general
qwen/qwen3-coder	coding, editing, technical

Low-Cost Tier

Model	Domains
google/gemini-3-flash-preview	coding, editing, technical
anthropic/claude-haiku-4.5	general, technical, reasoning
deepseek/deepseek-chat-v3.1	general, reasoning, technical, coding
deepseek/deepseek-v3.2	general, reasoning, technical, coding
openai/gpt-oss-120b	general, reasoning, search

Models are selected via embedding-based routing — query embeddings are matched to model domain profiles without an LLM call.

Tools

Research

Tool	Description
research	Async research (returns job_id)
conduct_research	Sync research with streaming
batch_research	Parallel batch queries
research_follow_up	Context-aware follow-up
agent	Unified entrypoint (auto-routes)

Knowledge Base

Tool	Description
search	Hybrid BM25+vector search
retrieve	Index or SQL query
query	SQL SELECT with params
get_report	Get report by ID
history	List recent reports

Session & Graph

Tool	Description
undo / redo	Session time-travel
checkpoint	Named save points
fork_session	Create alternate timeline
graph_traverse	Explore knowledge graph
graph_clusters	Find node clusters
graph_pagerank	Importance rankings

Rail Protocol

Tool	Description
list_rails	List rails, tunnels, routes, consensus
explain_rail	Detailed rail/tunnel config
list_routes	All defined routes
list_tunnels	Active agent-to-agent tunnels
list_consensus	Streaming consensus sessions

Utility

Tool	Description
ping	Health check
get_server_status	Full diagnostics
job_status	Check async job
date_time	Current timestamp
calc	Math evaluation
list_tools	Available tools

MCP Compliance

Compliant with MCP Specification 2025-11-25 (stable, AAIF/Linux Foundation governance).

Feature	SEP	Status
JSON-RPC 2.0	Core	Compliant
Tools/Resources/Prompts	Core	Compliant
Task Protocol	SEP-1686	Compliant
Sampling with Tools	SEP-1577	Compliant
Elicitation	SEP-1036	Compliant
MCP Apps	SEP-1865	Compliant
Enterprise Auth	SEP-990	Compliant
Client Metadata	SEP-991	Compliant

Full Compliance Report

Architecture

User Query
    │
    ▼
┌─────────────────┐
│  Planning Agent  │ ─── Decomposes into sub-queries
└────────┬────────┘
         │
    ┌────┴────┐
    ▼         ▼
┌───────┐ ┌───────┐
│Agent 1│ │Agent N│ ─── Parallel research (embedding-routed models)
└───┬───┘ └───┬───┘
    │         │
    ▼         ▼
┌─────────────────┐
│   Synthesizer   │ ─── Consensus + citations (Signal protocol)
└────────┬────────┘
         │
         ▼
┌─────────────────┐
│  Knowledge Base  │ ─── PGlite + pgvector (persistent)
└─────────────────┘

Core Abstractions

Module	Purpose
Signal Protocol	Inter-agent communication with confidence scoring and consensus
Rail Protocol	Bidirectional channels with backpressure, provenance, tunnels
Error Taxonomy	Deterministic classification with auto-learning and circuit breakers
Circuit Breaker	Model API fault tolerance with configurable thresholds and auto-recovery
Parameter Normalization	Declarative alias system (q→query, cost→costPreference)
RoleShift Protocol	Bidirectional server↔client via MCP sampling/elicitation
Embedding Router	Local vector-based model selection via @terminals-tech/embeddings

Circuit Breaker

Protects against cascading model API failures. Configurable via environment:

Variable	Default	Description
RAIL_CIRCUIT_BREAKER	true	Enable circuit breaker
RAIL_CIRCUIT_THRESHOLD	5	Failures before tripping
RAIL_CIRCUIT_RESET_MS	120000	Recovery timeout (ms)

States: closed (normal) -> open (failing, requests rejected) -> half-open (testing recovery).

Transport (v2.0.0)

Transport	Status	Use Case
Streamable HTTP	Primary	All new integrations
SSE	Deprecated	Legacy compatibility only
STDIO	Default	MCP clients (Claude, Jan AI, Continue)

Links

• Homepage: terminals.tech
• npm: @terminals-tech/openrouter-agents
• GitHub: terminals-tech/openrouter-agents
• Docs: CLAUDE.md | Tool Patterns | Getting Started

Releasing

Releases are automated via release-please:

1. Push conventional commits to main (e.g. feat:, fix:, chore:)
2. release-please opens a version-bump PR
3. Merge the PR → GitHub Release created automatically
4. npm publish triggers on release via CI

Manual publish:

npm test && npm publish --access public

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Version: 2.0.0 | MCP SDK: 1.27.1 | MCP Spec: 2025-11-25 | Author: Tej Desai | License: MIT