Agent Router

Local-first, quota-aware routing for AI coding agents in Herdr.

router is a command-line tool that picks an AI coding agent, model, and reasoning effort for a task, then starts that agent for you in a Herdr pane.

router run "implement the approved plan in docs/plans/billing.md"

It filters your subscriptions with fixed rules (enabled models, quota, the 40% reserve on shared accounts), asks TypeSafe to rank what is left and choose an effort, starts the chosen agent (Cursor, Claude Code, Codex, or OpenCode), and hands it the task.

Pre-release: the project is under active development. Review the security and privacy notes below before using real credentials or shared accounts.

Demo

Why Agent Router?

• Quota-aware: routes around depleted or reserved subscription capacity.
• Policy-first: deterministic eligibility rules run before semantic ranking.
• Local-first: configuration, usage snapshots, decisions, and session history stay on your machine unless an explicitly configured integration needs them.
• Agent-agnostic: supports Cursor, Claude Code, Codex, and OpenCode through one command.

Prerequisites

• Node.js 20 or newer (nvm use reads .nvmrc).
• A TypeSafe API key. Routing always calls TypeSafe; there is no fallback. Each run sends the task text to TypeSafe. Recognizable credentials are rejected locally before the call; do not place other sensitive narrative data in routing tasks.
• At least one agent CLI you are logged in to: agent (Cursor), claude (Claude Code), codex, or opencode. The router uses those logins; no provider API keys are needed.
• Herdr, to launch agents. router run without --dry-run only launches from inside a Herdr pane (HERDR_ENV=1).

Setup

1. Install and build

git clone https://github.com/nidhi-singh02/agent-router.git
cd model-router
npm install
npm run build

2. Put router on your PATH

npm link -w @model-router/router

Or add an alias to ~/.zshrc:

alias router="node $HOME/Code/model-router/packages/router/dist/cli.js"

After git pull, run npm run build again.

3. Create your config

The config lives in .model-router/ inside the repo (gitignored). Point the router at it from ~/.zshrc, then source ~/.zshrc:

export MODEL_ROUTER_HOME="$HOME/Code/model-router/.model-router"

mkdir -p .model-router
cp config.example.json .model-router/config.json

Without MODEL_ROUTER_HOME, the router uses ~/Library/Application Support/model-router on macOS (~/.config/model-router elsewhere).

4. Store the TypeSafe key in the macOS Keychain

security add-generic-password -a "$USER" -s model-router-typesafe -w

The command prompts for the key, so it never lands in shell history. The config refers to it with "typesafe": { "apiKeyRef": "keychain:model-router-typesafe" }. Every pane and agent then finds the key without exporting anything, and it stays out of agents' environments. To replace the key, add -U. If macOS asks to allow security access the first time, choose "Always Allow". TYPESAFE_API_KEY in the environment still works as a fallback.

5. Add your accounts

There is no router accounts add command. Edit the accounts array in .model-router/config.json (hidden folder; for example code .model-router/config.json) with one entry per agent login:

{
  "id": "acct_personal_claude",
  "label": "personal claude",
  "provider": "anthropic",
  "agent": "claude-code",
  "ownership": "personal",
  "collectorPreference": ["local-session"],
  "enabledModels": ["anthropic:claude-sonnet", "anthropic:claude-opus"],
  "enabled": true
}

Run router accounts to check that the file parses. docs/configuration.md has the full schema.

6. Install the model-router skill (optional, recommended)

The skill lets an agent route the next phase of your work (see Phases). Link the repo copy so updates arrive with git pull:

ln -s "$PWD/skills/model-router" ~/.claude/skills/model-router
ln -s "$PWD/skills/model-router" ~/.codex/skills/model-router
ln -s "$PWD/skills/model-router" ~/.cursor/skills/model-router

The links follow whatever branch is checked out in this repo.

Models

Defined in packages/router/config/models.json. Add an ID to an account's enabledModels to use it.

TypeSafe picks the effort from the model's list. ultra is only offered when your task text contains the word "ultra". Capability, cost, and latency numbers in models.json are estimates you can adjust.

Everyday use

router run "<task>" --dry-run    # see which agent, model, and effort would be used
router run "<task>"              # start that agent in a new Herdr pane and send the task
router status                    # list accounts; add --usage to show quota
router session                   # the latest launch; router session --list for more

--dry-run prints the decision card and the command it would start, without opening a pane or sending anything. A real run splits a new pane next to the current one, starts the agent, waits for it to finish starting up, sends the task, and confirms the agent began working. You can run the router any number of times, in the same tab or different ones; each launch gets its own agent name such as router-codex-3c356c.

The decision card

Selected: cursor / composer-2.5 / none
Phase: implementation
Why: TypeSafe selected acct_personal_cursor:cursor:composer-2.5 for implementation in phase implementation
Reserve policy: personal account
Cache decision: no previous session
Usage source: estimated local-session
Quota: auto 70% left (spend 45% left)
Freshness: refreshed at 2026-09-17T12:00:00.000Z

The router routes one phase per task (planning, implementation, debugging, review, research, and so on). It does not answer your question itself; the launched agent does.

Exit codes

Quota and usage

Usage checks on router run are local-session by default: the router reads status-line cache files (milliseconds) and persists non-unknown snapshots to SQLite. Official CLI/API and browser collectors stay behind --usage (slower, and some live commands may consume quota). Personal accounts stay eligible when quota is missing, stale, or at 0%. Shared accounts still need known usage above the reserve.

router status without --usage still lists accounts only. router status --usage runs the full collector chain.

Quota on the card is informational. For a personal account, a model at 0% remaining is still eligible. Shared accounts still exclude quota-exhausted and unknown-usage.

Where quota comes from

The Cursor, Claude Code, and Codex CLIs do not report plan usage on the command line. The router reads quota from cache files that your own status line scripts write; the router does not install those scripts. Enable it with "local-session" in the account's collectorPreference. Cache data older than 15 minutes counts as unknown, and a cache only refreshes while a session of that tool is open and redrawing its status line.

Cursor: ~/.cursor/statusline-quota-cache.json

{ "pct": 45, "auto_left": 70, "at": 1700000000 }

pct is the percent of included spend left (Grok models), auto_left the percent of the Auto pool left (Composer), and at the Unix time in seconds.

Claude Code: ~/.claude/statusline-quota-cache.json, written from the rate_limits Claude Code passes to its status line:

{
  "at": 1700000000,
  "five_hour": { "used_percentage": 20, "resets_at": 1700013600 },
  "seven_day": { "used_percentage": 10, "resets_at": 1700604800 }
}

Either window may be missing, and a window whose reset time has passed counts as fully available.

Codex: ~/.codex/statusline-quota-cache.json

{ "weekly_left": 40, "at": 1700000000 }

weekly_left is the percent of weekly quota remaining (0–100), and at is Unix time in seconds. The router does not write this file.

OpenCode: harness-only; quota belongs to the underlying provider.

Personal and shared accounts

• Personal: stays eligible even if quota is missing, stale, or at 0%. The card may still show remaining quota when a cache exists.
• Shared: needs known usage (a fresh local-session cache, or --usage) and keeps 40% of its quota in reserve. It is excluded when the coordinator reports someone else using it. Without a coordinator (the usual local setup), it routes on its quota alone.

Phases: planning, then implementation

Each router run records a session in .model-router/state.sqlite. A launched agent's task ends with Router session: <id> and instructions for when its phase is done. With the skill installed, the flow is:

The router repairs the state directory to 0700 and SQLite-related files to 0600 whenever it opens the database. Treat the task and handoff history as sensitive local data.

1. router run "plan feature X" starts, for example, Grok for planning.
2. The agent writes the plan to a file and asks you whether to route the next phase.
3. When you agree, it runs router session <id> and router run --session <id> "implement the plan in docs/plans/x.md" --dry-run, shows you the card, and launches without --dry-run after you confirm.
4. The new session records the previous one. The card shows Previous session: <id> (planning -> implementation), and the new agent gets the previous phase and task.

The next agent starts in a new pane without the earlier conversation, so the task must point to the file. You can run the same commands yourself:

router session <id>
router run --session <id> "implement the plan in docs/plans/x.md"

Commands

router run "<task>" [--dry-run] [--usage] [--session <id>] [--json]
router status [--usage]
router session [id] [--list] [--limit <n>] [--json]
router accounts
router usage refresh [--source local-session|official-cli|browser] [--dry-run]

--json prints machine-readable output for plugins, including sessionId, agentName, and paneId. router usage refresh defaults to local-session file reads; --dry-run prints facts and does not persist. Without --dry-run it writes snapshots to SQLite.

Herdr plugin

Agent Router also ships as a Herdr plugin, so routing, status, sessions, and usage refresh are reachable from Herdr actions and keybindings instead of a shell prompt:

herdr plugin install nidhi-singh02/agent-router
herdr plugin action list --plugin nidhi-singh02.agent-router

The manifest is herdr-plugin.toml at the repository root; the scripts it runs live in herdr-plugin/. See herdr-plugin/README.md for the action list, keybinding examples, and local development with herdr plugin link.

Troubleshooting

Development

npm run verify   # typecheck, lint, format check, tests, build
npm test         # tests only

Do not deploy the Cloudflare coordinator (packages/coordinator) or write into an external Hermes checkout (packages/hermes-heartbeat) without explicit approval. See docs/ for configuration, operations, privacy, and provider support.

Security and privacy

• Never commit .model-router/, .env, API keys, bearer tokens, cookies, or provider cache files. The repository ignores the local state directories and environment files by default.
• Store the TypeSafe key in the macOS Keychain as shown above. Environment variables are a supported fallback, but are easier to expose accidentally through child processes or logs.
• Task text is sent to TypeSafe for classification and ranking. Do not route secrets, credentials, private client data, or other sensitive text.
• router run starts local agent processes with the permissions of your current user. Review the selected route and task before launching it.
• The optional coordinator and heartbeat packages are not required for ordinary personal accounts. Treat them as pre-release components and review their deployment configuration before exposing them to a network.

See Privacy, Operations, and Configuration for the detailed data flow and deployment guidance.

Contributing

Issues and focused pull requests are welcome. Before opening a pull request, run:

npm run verify

Please do not include credentials, private account data, local quota caches, generated state, or provider dashboard exports in issues, tests, or commits.

License

Agent Router is available under the MIT License.