specification: API Commons Rate Limits
specificationVersion: '0.1'
schema: https://raw.githubusercontent.com/api-evangelist/interface-research/main/schema/api-commons.yml#/$defs/RateLimits
provider: Zeroheight
providerId: zeroheight
created: '2026-05-04'
modified: '2026-08-28'
generated: '2026-08-28'
method: searched
source: >-
  https://www.postman.com/zeroheight-0379/zeroheight/overview (zeroheight's own public Postman
  collection, saved verbatim at postman/zeroheight-api.postman_collection.json) ;
  https://help.zeroheight.com/hc/en-us/articles/48004395674011-zeroheight-MCP-overview
tags:
  - Rate Limiting
  - Quotas
  - Throttling
description: >-
  Published zeroheight rate limits. Replaces a 2026-05-04 scaffold that carried invented per-tier
  numbers (10/100/1000 rpm) — those were never zeroheight's and have been removed. zeroheight
  publishes exactly one REST limit, applied per API key, plus a separate monthly call cap on the MCP
  surface for Free and Starter plans.
headers:
  limit: X-RateLimit-Limit
  remaining: X-RateLimit-Remaining
  reset: X-RateLimit-Reset
responseCodes:
  throttled: 429
header_semantics:
  X-RateLimit-Limit: The maximum number of requests that the consumer is permitted to make per minute.
  X-RateLimit-Remaining: The number of requests remaining in the current rate limit window.
  X-RateLimit-Reset: The time at which the current rate limit window resets, in UTC epoch seconds.
limits:
  - name: REST API per-key limit
    scope: api-key
    metric: requests
    limit: 30
    timeFrame: 30 seconds
    window_seconds: 30
    surface: https://zeroheight.com/open_api/v2
    applies:
      - Zeroheight API
    source: zeroheight public Postman collection, "Rate and usage limits"
    quote: 'API access rate limits apply at a per-API key basis in unit time. The limit is 30 requests per 30 seconds.'
  - name: MCP monthly call cap (Free and Starter)
    scope: plan
    metric: mcp_calls
    limit: 500
    timeFrame: month
    surface: https://mcp.zeroheight.com/mcp
    applies:
      - zeroheight MCP
    source: https://help.zeroheight.com/hc/en-us/articles/48004395674011-zeroheight-MCP-overview
    note: Free and Starter are capped at 500 MCP calls per month and do not include the fast search tool. Enterprise gets higher limits, not publicly numbered.
limit_count: 2
gaps:
  - No Retry-After header is documented, and no RateLimit-Policy / draft RFC 9238-style headers are used — only the three X-RateLimit-* headers.
  - The 429 body shape is not documented; by observation of the live API every error uses the same {status,message,data.request_id} envelope.
  - The header description says "per minute" while the published limit is per 30 seconds. zeroheight's own docs are internally inconsistent here; both are recorded verbatim rather than reconciled.
  - Enterprise MCP limits are described only as "higher limits" with no number.
policies:
  - name: Plan gating
    description: REST API access is an Enterprise-plan feature. Free and Starter accounts cannot call the REST API at all, which is a harder limit than any rate.
maintainers:
  - FN: Kin Lane
    email: kin@apievangelist.com