Configuration

Every field in meted.config.json, and every environment override.

meted.config.json lives at the root of your project and is meant to be committed. apiKeyEnv holds the name of the environment variable your provider key lives in, never the key.

{
  "$schema": "https://meted.dev/schema/v0.1.json",
  "version": 1,
  "mode": "observe",
  "provider": {
    "id": "openai",
    "baseUrl": "https://api.openai.com/v1",
    "apiKeyEnv": "OPENAI_API_KEY",
    "headers": {},
  },
  "gateway": {
    "host": "127.0.0.1",
    "port": 8787,
    "requestTimeoutMs": 120000,
    "responseHeaders": true,
  },
  "engine": {
    "module": null,
    "wasm": null,
    "exportName": null,
    "timeoutMs": 250,
    "options": {},
  },
  "policy": {},
  "cloudflare": {
    "workerName": "meted-gateway",
    "accountId": null,
    "routes": [],
    "compatibilityDate": "2025-01-01",
  },
}

A broken configuration never stops a running gateway. Unreadable fields fall back to their defaults and are reported as warnings.

`mode`

observe | conservative | balanced | aggressive. Default observe. See Policies.

`provider`

Field	Default
`id`	`openai`	Adapter id
`baseUrl`	OpenAI	Upstream base URL
`apiKeyEnv`	`OPENAI_API_KEY`	Name of the variable holding the key
`headers`	`{}`	Extra headers forwarded upstream. Non-secret only

`gateway`

Field	Default
`host`	`127.0.0.1`	Bind address
`port`	`8787`	Port
`requestTimeoutMs`	`120000`	Upstream timeout. Streams are exempt once started
`responseHeaders`	`true`	Add `x-meted-*` headers

`engine`

Field	Default
`module`	`null`	Package name or path exporting an engine
`wasm`	`null`	Path to a WASM engine
`exportName`	`null`	Named export to use
`timeoutMs`	`250`	Past this, the engine counts as failed
`options`	`{}`	Passed to the engine factory

`policy`

Overrides for the current mode. Every field is optional.

Field
`ceilingMultiplier`	Multiplier on the engine's ceiling
`floorTokens`	The applied ceiling is never lower than this
`minConfidence`	Below this, forward unchanged
`lengthHint`	Append a length hint to the prompt

{
  "mode": "balanced",
  "policy": { "minConfidence": 0.7 },
}

`cloudflare`

Used by meted deploy.

Field	Default
`workerName`	`meted-gateway`	Worker name
`accountId`	`null`	Written into `wrangler.toml` when set
`routes`	`[]`	Route patterns for the Worker
`compatibilityDate`	`2025-01-01`	Workers compatibility date

Environment overrides

Environment variables win over the file, so one committed config can behave differently per deployment.

Variable	Overrides
`METED_MODE`	`mode`
`METED_HOST`, `METED_PORT`	`gateway.host`, `gateway.port`
`METED_PROVIDER_BASE_URL`	`provider.baseUrl`
`METED_PROVIDER_API_KEY_ENV`	`provider.apiKeyEnv`
`METED_ENGINE_MODULE`	`engine.module`
`METED_ENGINE_WASM`	`engine.wasm`
`METED_DEBUG`	Print stack traces on CLI errors

Meted walks up from the working directory looking for meted.config.json, so commands work from anywhere inside a project. With no config file, defaults are used and the CLI prints No meted.config.json here. Using defaults.