generated: '2026-08-13'
method: searched
source: >-
  https://status.substack.com/, https://substack.com/changelog,
  https://substack.com/api-tos
versioning:
  scheme: uri-path
  current: v1
  evidence: >-
    Every Substack API path observed carries an explicit /api/v1/ segment — the MCP
    endpoint https://mcp.substack.com/api/v1/mcp and the web application's own JSON
    endpoints (https://{publication}.substack.com/api/v1/posts). No header, date or
    train versioning was observed.
  policy_published: false
  note: >-
    Substack publishes no versioning policy. The only version commitment in writing is
    in the Developer API Terms of Use, which reserves the right to "modify or
    discontinue the API or these API Terms at any time" with no notice period.
deprecation:
  policy_url: null
  policy_published: false
  sunset_header: false
  note: >-
    No deprecation policy, no RFC 8594 Sunset/Deprecation header support observed, and
    no advance-notice commitment. Section 12 of the API Terms
    (https://substack.com/api-tos) is the closest thing and it is the opposite of a
    deprecation policy: modification or discontinuation at any time, effective on
    continued use. Section 9 permits immediate suspension or termination of an
    individual integrator's access with or without notice. No Deprecation pointer is
    emitted for this provider because there is no policy to point at.
sla:
  url: null
  uptime_target: null
  note: >-
    No published SLA or uptime target. The API Terms disclaim all warranties and
    provide the API "as is" and "as available".
status_page:
  url: https://status.substack.com/
  provider: Atlassian Statuspage
  page_id: 3fzngjd16vw0
  alternate_url: https://substack.statuspage.io
  api: https://substack.statuspage.io/api/v2/summary.json
  api_status: 200
  components:
    - Substack publications
    - Writer dashboards
    - Email delivery
    - Subscription invoice processing
    - Substack.com
    - Push Notifications
    - Custom domains
  note: >-
    The status page covers the consumer and creator platform. Neither the MCP server
    nor the Developer API appears as a component, so an agent depending on
    mcp.substack.com has no status signal for the surface it actually calls.
    https://status.substack.com/api/v2/summary.json returns the HTML page rather than
    JSON; the machine-readable summary is served from the statuspage.io hostname.
changelog:
  url: https://substack.com/changelog
  artifact: changelog/substack-changelog.yml
deprecated_operations: []
milestones:
  - date: '2026-01-08'
    event: Substack Developer API Terms of Use last updated
    source: https://substack.com/api-tos
  - date: '2026-04-21'
    event: Substack Developer API support article last updated (per provider-stated date)
    source: https://support.substack.com/hc/en-us/articles/45099095296916-Substack-Developer-API
  - date: '2026-08-07'
    event: >-
      "How to connect Substack to your AI Assistant" (the official MCP server
      documentation) last updated
    source: https://support.substack.com/api/v2/help_center/en-us/articles/50834026608916.json
x-evidence:
  - fetched: '2026-08-13'
    url: https://substack.statuspage.io/api/v2/summary.json
    http_status: 200
  - fetched: '2026-08-13'
    url: https://substack.com/changelog
    http_status: 200
  - fetched: '2026-08-13'
    url: https://substack.com/api-tos
    http_status: 200