Enable detailed logging of the request processing lifecycle.

const mock = schmock({ debug: true })

Every [SCHMOCK:CATEGORY] line is prefixed with an ISO timestamp — [2024-01-01T00:00:00.000Z] [SCHMOCK:CONFIG] … — omitted from the samples below for brevity. The category is the internal name uppercased, so grep SCHMOCK:LIFECYCLE works. The [SCHMOCK] request-<id> timing line comes from console.time/timeEnd and carries no timestamp of its own.

[SCHMOCK:CONFIG] Debug mode enabled
[SCHMOCK:CONFIG] Callable mock instance created { debug: true, namespace: undefined, delay: undefined }
[SCHMOCK:ROUTE] Route defined: GET /users
[SCHMOCK:PLUGIN] Registered plugin: auth@1.0.0

[SCHMOCK:REQUEST] [abc123] GET /users { headers: {...}, query: { limit: '10' }, bodyType: 'none' }
[SCHMOCK:ROUTE] [abc123] Matched route: GET /users
[SCHMOCK:PIPELINE] Running plugin pipeline for 2 plugins
[SCHMOCK:PIPELINE] Processing plugin: auth
[SCHMOCK:PIPELINE] Processing plugin: faker
[SCHMOCK:PIPELINE] Plugin faker generated response
[SCHMOCK:RESPONSE] [abc123] Sending response 200 { status: 200, headers: {...}, bodyType: 'object' }
[SCHMOCK] request-abc123: 25.678ms

[SCHMOCK:ERROR] [def456] Error processing request: Authentication required
[SCHMOCK:PIPELINE] Plugin auth handled error
[SCHMOCK:RESPONSE] [def456] Sending response 500 { status: 500, headers: {...}, bodyType: 'object' }
[SCHMOCK:EVENT] request:end listener rejected: metrics backend unavailable
[SCHMOCK] request-def456: 15.234ms

A request that ends in a 500 still finishes through the normal response path, so it is logged as RESPONSE, recorded in history, and reported to request:end listeners.

[SCHMOCK:SERVER] Listening on 127.0.0.1:3000
[SCHMOCK:SERVER] Server stopped
[SCHMOCK:LIFECYCLE] Interception lease acquired (1 held)
[SCHMOCK:LIFECYCLE] Interception lease released (0 still held)
[SCHMOCK:LIFECYCLE] Request history cleared
[SCHMOCK:LIFECYCLE] Mock fully reset

These eleven are the complete set — packages/core is the only emitter, and a unit test pins the list so it cannot drift from this table.

Request and response header values are redacted in REQUEST and RESPONSE logs when the header name is one of authorization, proxy-authorization, cookie, set-cookie, x-api-key, x-auth-token or x-schmock-admin-token (matched case-insensitively). The header NAME is still logged so you can see it was present; only the value is replaced with [redacted]:

[SCHMOCK:REQUEST] [abc123] GET /users { headers: { authorization: '[redacted]', 'content-type': 'application/json' }, query: {}, bodyType: 'none' }

Redaction affects logs only — plugins, generators and history() still receive the real header values. There is no opt-out. The set is exported from @schmock/core as SENSITIVE_HEADER_NAMES, and redactHeaders() applies the same masking; see Header helpers.

bodyType reports the type of the request body whenever one was supplied, so an empty string, 0 or false show as string / number / boolean; none means no body was passed at all.

An intercepted fetch that no route matches (passthrough on, no beforeRequest hook) also logs bodyType: 'none', because its body is never read.

# Only pipeline logs
bun start | grep "SCHMOCK:PIPELINE"

# Only errors
bun start | grep "SCHMOCK:ERROR"

# Specific request
bun start | grep "abc123"

const mock = schmock({
  debug: process.env.NODE_ENV === 'development',
})

The OpenAPI plugin has its own debug option that logs CRUD detection:

mock.pipe(await openapi({
  spec: './api.yaml',
  debug: true,
}))

[@schmock/openapi] Detected 3 CRUD resources, 2 static routes
[@schmock/openapi] users: list=wrapped("data"), error=schema(404), headers=2