generated: '2026-08-12'
method: searched
source: >-
  https://www.npmjs.com/package/@rb2b/rb2b-apis-mcp — RB2B's own published MCP
  server states "Rate limit: 50 requests/second per endpoint" in its README and
  repeats it verbatim in every paid tool description; dist/api.js maps HTTP 429
  to that message.
provider: RB2B
providerId: rb2b
description: >-
  RB2B publishes exactly one rate limit, and it is published inside an npm
  package rather than on a documentation site: 50 requests per second per
  endpoint on the Identity / Enrichment API. No limit is published for the OEM
  Partner API. No RateLimit-* / X-RateLimit-* / Retry-After header was observed
  on any response, so a client has no runtime signal — only the documented
  number and a 429 when it is crossed. The real throughput constraint in
  practice is the prepaid credit balance, not the per-second ceiling.
limit_count: 1
headers:
  rate_limit: none observed
  remaining: none observed
  reset: none observed
  retry_after: none observed
  request_id: x-request-id
  note: >-
    Headers were read from live 401 responses on 2026-08-12
    (api.rb2b.com/api/v1/credits, app.rb2b.com/api/v1/credit_usage,
    app.rb2b.com/api/v1/domains). Only x-request-id and x-runtime appear
    alongside the standard security headers. An authenticated 2xx was not
    exercised, so the absence is recorded as "none observed on the responses
    available to an anonymous client", not as a proof for all responses.
response_codes:
  throttled: 429
limits:
  - name: Identity / Enrichment API requests
    surface: https://api.rb2b.com/api/v1
    scope: per-endpoint
    metric: requests_per_second
    limit: 50
    burst: null
    window: second
    applies_to: all Identity and Enrichment endpoints
    source: https://www.npmjs.com/package/@rb2b/rb2b-apis-mcp
  - name: OEM Partner API requests
    surface: https://app.rb2b.com/api/v1
    scope: unknown
    metric: null
    limit: null
    window: null
    source: null
    note: >-
      No rate limit is published for add_domain, delete_domain, domains or
      credit_usage. Recorded as an honest gap.
quota:
  model: prepaid credits
  note: >-
    Credits, not requests, are the binding constraint. Each successful Identity
    call costs 1-4 credits; the balance is readable at GET /credits and the
    account is refused when it runs out. Platform plans meter "resolutions" per
    month with per-resolution overage — see plans/rb2b-plans-pricing.yml.
gaps:
  - Rate limit is documented only inside an npm package, not on any RB2B web page.
  - No RateLimit-*/Retry-After headers, so clients cannot pace from the response.
  - No published limit at all for the OEM Partner API.