Messaging API

A template and concept entry for messaging APIs. This represents the pattern and structure for messaging API implementations used in storytelling, training, and knowledge bases.

Messaging API publishes 1 API contract indexed on the APIs.io network: Messages API. Tagged areas include API Pattern, Messaging, and Templates.

The Messaging API catalog on APIs.io includes 1 Spectral governance ruleset.

Messaging API’s developer surface includes authentication and 4 more developer resources.

📡 Profile data on GitHub

23.3/100 emerging ▬ flat Agent 31/100 agent ready Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessFreemiumSelf serve

1 published contract

API PatternMessaging Templates

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 23.3/100 · emerging

Contract Quality 10.4 / 19

Developer Ergonomics 1.8 / 15

Access Clarity 1.2 / 15

Operational Transparency 0.8 / 10

Contract Governance 1.2 / 9

Discoverability 3.6 / 8

Regulatory Posture 0.9 / 15

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 31/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 5 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

The six quality facets above are damped to 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship
Idempotency +9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented)
Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document
Delegated User Identity +6 pts — a served discovery document listing authorization_code in grant_types_supported (served), else an oauth2 authorizationCode flow or openIdConnect declared in an OpenAPI (documented)

8 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Access Clarity scores 7.9 — up to +18.4 composite points
Developer Ergonomics scores 11.9 — up to +17.6 composite points
Operational Transparency scores 7.9 — up to +12.0 composite points

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/messaging-api/apis.yml: open an issue on github.com/api-evangelist/messaging-api to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Standards implemented 1

Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.

OpenAPI

measured — observed by APIs.io (published)

APIs 1

Individual APIs this provider publishes, each with its own machine-readable definition.

Messaging API Messages API

Managing, sending, and receiving of messages via SMS and other channels.

Open Collections 2

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Messaging API Messages API

OPEN COLLECTION

Messaging API Messages API

OPEN COLLECTION

Messaging API pricing

Not yet checked against Messaging API's own pricing page. Compiled by API Evangelist on 2026-05-04; confirm before you rely on a figure. A free plan or tier is listed.

Plan	Price
Free freemium	Free
Professional paid	Free
Enterprise enterprise	—

Plan details, limits and sources →

Rate limits

Free Tier Default: 10 requests per minute
Free Tier Monthly Quota: 1000 requests per month
Professional Tier Default: 100 requests per minute

Compiled by API Evangelist, not yet checked against Messaging API's documentation. All 5 limits →

Pricing Plans 1

Published pricing tiers and plan structures.

Messaging Api Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Messaging Api Rate Limits

5 limits

RATE LIMITS

Service Levels 1

Uptime the provider promises or reports, as SLA4OAI. Read from its own pages; APIs.io runs no monitors.

Messaging API

SLA

FinOps 1

Cost, billing, and metering signals for API financial operations.

Messaging Api Finops

FINOPS

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Messaging API API Rules

64 rules · 62 errors 1 warnings 1 info

SPECTRAL

Security Posture 1

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Messaging Api Authentication

apiKey · 1 scheme

SECURITY

Agentic Access 1

Recommended x-agentic-access execution contracts for AI agents.

Messaging Api Agentic Access

6 operations · 4 acting

AGENTIC

Resources

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Access & Security 1

Authentication, authorization, and security posture

Authentication

Authentication

Operate 1

Status, limits, changes, and where to get help

RateLimits

RateLimits

Commercial 2

Pricing, plans, and the legal terms of use

Plans

Plans

FinOps

FinOps

Source (apis.yml)

aid: messaging-api
name: Messaging API
description: A template and concept entry for messaging APIs. This represents the pattern and structure for messaging API
  implementations used in storytelling, training, and knowledge bases.
type: Index
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: false
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - openapi
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: false
  public: false
  gated: none
  gated_source:
  - onboarding
  label: Freemium · Self-serve signup
  confidence: medium
  try_now_blocked_by: example-domain
  source:
  - plans
  - authentication
  generated: '2026-11-06'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/messaging-api.png
url: https://raw.githubusercontent.com/api-evangelist/messaging-api/refs/heads/main/apis.yml
tags:
- API Pattern
- Messaging
- Templates
tags_raw:
- API Pattern
- Messaging
- Template
created: '2024-12-29'
modified: '2026-05-19'
specificationVersion: '0.23'
apis:
- aid: messaging-api:messaging-api-messages-api
  name: Messaging API Messages API
  description: Managing, sending, and receiving of messages via SMS and other channels.
  humanURL: https://example.com/messages
  baseURL: https://api.example.com
  tags:
  - Message
  tags_raw:
  - Messages
  properties:
  - type: OpenAPI
    url: openapi/messaging-api-messages-api-openapi.yml
common:
- type: Plans
  url: plans/messaging-api-plans-pricing.yml
- type: RateLimits
  url: rate-limits/messaging-api-rate-limits.yml
- type: FinOps
  url: finops/messaging-api-finops.yml
- type: AgenticAccess
  url: agentic-access/messaging-api-agentic-access.yml
- type: Authentication
  url: authentication/messaging-api-authentication.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

Messaging API — frequently asked questions

Does Messaging API have an API?

Yes. APIs.io lists 1 API from Messaging API, including Messaging API Messages API.

Is there an OpenAPI specification for the Messaging API?

Yes. APIs.io indexes 1 OpenAPI specification for Messaging API, each linked for download from this page.

How do I authenticate with the Messaging API?

Messaging API uses bearer-token authentication (apiKey · 1 scheme). The details are profiled on APIs.io as Messaging Api Authentication.

How much does the Messaging API cost?

APIs.io lists 3 pricing plans for Messaging API, with each plan's price, limits and inclusions under Pricing on this page.

Is the Messaging API ready for AI agents?

Messaging API has a Kin Score of 23.3 out of 100 (emerging) and an Agent Readiness score of 31.3 (agent-ready), scored by API Evangelist on 2026-11-06.

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get_provider_toolsEvery MCP tool they ship, with the operation each wraps.
get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.
get_provider_ratingPRO — composite, band, trend and facet scores.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
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