overlay: 1.0.0
info:
title: API Evangelist enhancements for Stannp Direct Mail Account Postcards API
version: 1.0.0
x-generated: '2026-08-13'
x-method: generated
x-source: https://www.stannp.com/us/direct-mail-api/guide
extends: openapi/stannp-postcards-api-openapi.yml
actions:
- target: $.info
description: Record API Evangelist provenance and the artifacts derived from this spec.
update:
x-apievangelist-profile: https://apis.io/provider/stannp/
x-apievangelist-source: https://www.stannp.com/stannp-api-llm.md
x-apievangelist-artifacts:
conventions: conventions/stannp-conventions.yml
authentication: authentication/stannp-authentication.yml
errors: errors/stannp-problem-types.yml
rate-limits: rate-limits/stannp-rate-limits.yml
sandbox: sandbox/stannp-sandbox.yml
webhooks: asyncapi/stannp-webhooks.yml
data-model: data-model/stannp-data-model.yml
llms: llms/stannp-llms.txt
- target: $.components.securitySchemes
description: 'Stannp documents a second, spec-absent auth transport: the API key may be sent as an `api_key`
query parameter instead of HTTP Basic. Added here rather than in the harvested spec. See authentication/stannp-authentication.yml.'
update:
apiKeyQuery:
type: apiKey
in: query
name: api_key
description: 'Alternative to HTTP Basic: append ?api_key={API_KEY}. Documented at https://www.stannp.com/us/direct-mail-api/guide.
Note that a key in the query string is logged by proxies, CDNs and access logs; HTTP Basic is
the safer option.'
- target: $.servers
description: Region is selected by host, not by parameter, and a key authenticates only against the
region it was issued in.
update:
- url: https://api-us1.stannp.com/v1
description: 'US / CA API server. Defaults: US-LETTER letters, 4x6 postcards.'
- url: https://api-eu1.stannp.com/v1
description: 'EU / UK API server. Defaults: A4 letters, A6 postcards.'
- target: $.tags[?(@.name=='Postcards')]
description: Cross-link the tag to the API Evangelist data model.
update:
x-apievangelist-data-model: data-model/stannp-data-model.yml
- target: $.paths['/postcards/create'].post
description: Stannp supports idempotent retries on this operation via an `idempotency_key` request parameter.
A replay returns the ORIGINAL response body with HTTP 409 — treat 409 as success, not failure.
update:
x-idempotency:
supported: true
mechanism: request-parameter
parameter: idempotency_key
replay_status: 409
replay_body: original response body
match: full request body
docs: https://www.stannp.com/us/direct-mail-api/idempotency-keys
x-test-mode:
parameter: test
default: false
effect: returns a proof PDF, dispatches nothing, charges nothing
warning: test defaults to false — omitting it posts real physical mail
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