Anthropic

Anthropic is an AI safety company and the creator of the Claude family of large language models (Opus, Sonnet, Haiku, and the Fable/Mythos frontier line). The Claude Developer Platform exposes them through a single REST API at api.anthropic.com: the Messages API for text, vision, tool use, thinking, streaming and structured outputs; Message Batches for asynchronous work at half price; Files, Token Counting, Models, and experimental Prompt Tools; Managed Agents with sessions, environments, memory stores, vaults and scheduled deployments; a Skills API; and an Admin API for organizations, workspaces, members, invites and API keys. Authentication is x-api-key with a required anthropic-version date header and dated anthropic-beta opt-ins. Anthropic also authors two of the open standards the agent ecosystem runs on — the Model Context Protocol and the Agent Skills specification — and ships Claude Code, the terminal agentic coding tool, which doubles as a first-party stdio MCP server.

Anthropic publishes 43 APIs on the APIs.io network, including Messages API, Models API, Files API, and 40 more. Tagged areas include Artificial Intelligence, Claude, Foundation Models, Large Language Models, and Machine-Learning.

The Anthropic catalog on APIs.io includes 2 event-driven AsyncAPI specifications, 1 JSON-LD context, and 2 Spectral governance rulesets.

Anthropic’s developer surface includes authentication, changelog, CLI, documentation, developer portal, support, pricing, and 132 more developer resources.

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77.8/100 exemplar ▬ flat Agent 38/100 agent ready saas Full breakdown ↓
scored 2026-09-08 · rubric v0.20.0

AccessPaid

6 APIs 26 Features

Artificial Intelligence Claude Foundation Models Large Language Models Machine-Learning MCP Agents

Kin Score

Kin Score How this is scored →
scored 2026-09-08 · rubric v0.20.0

Composite quality — 77.8/100 · exemplar

Contract Quality 17.5 / 23

Developer Ergonomics 17.4 / 18

Access Clarity 13.7 / 18

Operational Transparency 8.3 / 12

Contract Governance 3.4 / 11

Discoverability 6.8 / 9

Create-or-Update Ergonomics 3.9 / 10

Agent readiness — 38/100 · agent ready

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 6 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 6 / 6

Agent Skills 5 / 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

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.

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 github.com/api-evangelist/anthropic: open an issue to ask a question, or submit a pull request to add artifacts. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

APIs 43

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

Anthropic Messages API

Send a structured list of input messages with text and/or image content, and the model will generate the next message in the conversation. The Messages API supports text, images...

Anthropic Models API

List and inspect Claude models including Opus 4.7, Sonnet 4.6, and Haiku 4.5. The response includes max_input_tokens, max_tokens, and a capabilities object for every model so cl...

Anthropic Files API

The Files API lets you upload and manage files for reuse across Messages, Batches, code execution, and Managed Agents without re-uploading content. 500 MB request limit; support...

Anthropic Skills API

Create and manage custom Agent Skills. Skills are filesystem-based directories of instructions, scripts, and resources that Claude loads on demand via progressive disclosure. Wo...

Anthropic Agents API

Reusable, versioned agent configurations

Anthropic Api Keys API

Monitor and manage API keys

Anthropic Cost API

Service-level cost reporting

Anthropic Environments API

Container configuration for agent sessions

Anthropic Events API

User messages and tool results sent to a session

Anthropic Organization API

Retrieve organization information and settings

Anthropic Organization Invites API

Create and manage organization invitations

Anthropic Organization Members API

Manage organization members and their roles

Anthropic Prompt Generation API

APIs for generating well-written prompts for specified tasks

Anthropic Prompt Improvement API

APIs for enhancing existing prompts with feedback

Anthropic Prompt Templatization API

APIs for converting prompts into reusable templates with variables

Anthropic Sessions API

Stateful agent execution instances

Anthropic Usage API

Token usage and consumption reporting

Anthropic Workspace Members API

Manage workspace membership and roles

Anthropic Workspaces API

Create and manage workspaces within an organization

Anthropic Agents?beta=true API

The Agents?beta=true API from Anthropic — 1 operation(s) for agents?beta=true.

Anthropic Anthropic API

The Anthropic API API from Anthropic — 0 operation(s) for anthropic api.

Anthropic Complete API

The Complete API from Anthropic — 1 operation(s) for complete.

Anthropic Deployment Runs API

The Deployment Runs API from Anthropic — 1 operation(s) for deployment runs.

Anthropic Deployment Runs?beta=true API

The Deployment Runs?beta=true API from Anthropic — 1 operation(s) for deployment runs?beta=true.

Anthropic Deployments API

The Deployments API from Anthropic — 5 operation(s) for deployments.

Anthropic Deployments?beta=true API

The Deployments?beta=true API from Anthropic — 1 operation(s) for deployments?beta=true.

Anthropic Dreams API

The Dreams API from Anthropic — 3 operation(s) for dreams.

Anthropic Dreams?beta=true API

The Dreams?beta=true API from Anthropic — 1 operation(s) for dreams?beta=true.

Anthropic Environments?beta=true API

The Environments?beta=true API from Anthropic — 1 operation(s) for environments?beta=true.

Anthropic Files?beta=true API

The Files?beta=true API from Anthropic — 1 operation(s) for files?beta=true.

Anthropic Memory Stores API

The Memory Stores API from Anthropic — 7 operation(s) for memory stores.

Anthropic Memory Stores?beta=true API

The Memory Stores?beta=true API from Anthropic — 1 operation(s) for memory stores?beta=true.

Anthropic Messages?beta=true API

The Messages?beta=true API from Anthropic — 1 operation(s) for messages?beta=true.

Anthropic Models?beta=true API

The Models?beta=true API from Anthropic — 1 operation(s) for models?beta=true.

Anthropic Organizations API

The Organizations API from Anthropic — 43 operation(s) for organizations.

Anthropic Sessions?beta=true API

The Sessions?beta=true API from Anthropic — 1 operation(s) for sessions?beta=true.

Anthropic Skills?beta=true API

The Skills?beta=true API from Anthropic — 1 operation(s) for skills?beta=true.

Anthropic Tunnels API

The Tunnels API from Anthropic — 7 operation(s) for tunnels.

Anthropic Tunnels?beta=true API

The Tunnels?beta=true API from Anthropic — 1 operation(s) for tunnels?beta=true.

Anthropic User Profiles API

The User Profiles API from Anthropic — 2 operation(s) for user profiles.

Anthropic User Profiles?beta=true API

The User Profiles?beta=true API from Anthropic — 1 operation(s) for user profiles?beta=true.

Anthropic Vaults API

The Vaults API from Anthropic — 6 operation(s) for vaults.

Anthropic Vaults?beta=true API

The Vaults?beta=true API from Anthropic — 1 operation(s) for vaults?beta=true.

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Postman Collections 11

Ready-to-run Postman collections for exercising this provider's APIs.

Anthropic Admin API

POSTMAN

Anthropic Claude Code Analytics API

POSTMAN

Anthropic Files API

POSTMAN

Anthropic Managed Agents API

POSTMAN

Anthropic Message Batches API

POSTMAN

Anthropic Messages API

POSTMAN

Anthropic Models API

POSTMAN

Anthropic Prompt Tools API

POSTMAN

Anthropic Skills API

POSTMAN

Anthropic Token Counting API

POSTMAN

Anthropic Usage and Cost API

POSTMAN

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Open Collections 29

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

API Collection

OPEN COLLECTION

Anthropic Admin API

OPEN COLLECTION

Anthropic Admin Agents API

OPEN COLLECTION

Anthropic Admin Agents Api Keys API

OPEN COLLECTION

Anthropic Admin Agents Claude Code Analytics API

OPEN COLLECTION

Anthropic Admin Agents Cost API

OPEN COLLECTION

Anthropic Admin Agents Environments API

OPEN COLLECTION

Anthropic Admin Agents Events API

OPEN COLLECTION

Anthropic Admin Agents Files API

OPEN COLLECTION

Anthropic Managed Agents API

OPEN COLLECTION

Anthropic Admin Agents Message Batches API

OPEN COLLECTION

Anthropic Admin Agents Messages API

OPEN COLLECTION

Anthropic Admin Agents Models API

OPEN COLLECTION

Anthropic Admin Agents Organization API

OPEN COLLECTION

Anthropic Admin Agents Organization Invites API

OPEN COLLECTION

Anthropic Admin Agents Organization Members API

OPEN COLLECTION

Anthropic Admin Agents Prompt Generation API

OPEN COLLECTION

Anthropic Admin Agents Prompt Improvement API

OPEN COLLECTION

Anthropic Admin Agents Prompt Templatization API

OPEN COLLECTION

Anthropic Prompt Tools API

OPEN COLLECTION

Anthropic Admin Agents Sessions API

OPEN COLLECTION

Anthropic Admin Agents Skill Versions API

OPEN COLLECTION

Anthropic Admin Agents Skills API

OPEN COLLECTION

Anthropic Admin Agents Token Counting API

OPEN COLLECTION

Anthropic Admin Agents Tokens API

OPEN COLLECTION

Anthropic Admin Agents Usage API

OPEN COLLECTION

Anthropic Usage and Cost API

OPEN COLLECTION

Anthropic Admin Agents Workspace Members API

OPEN COLLECTION

Anthropic Admin Agents Workspaces API

OPEN COLLECTION

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Arazzo Workflows 11

Multi-step API workflows described with the Arazzo specification.

Anthropic Cancel a Message Batch and Confirm

Create a batch, request cancellation, then poll until it leaves the canceling state.

ARAZZO

Anthropic Create Batch, Poll, and Retrieve Results

Submit a message batch, poll until processing ends, then fetch the JSONL results.

ARAZZO

Anthropic Count Tokens Then Create Message

Estimate input token usage for a prompt, then send the message only when it fits a budget.

ARAZZO

Anthropic Create Workspace and Add a Member

Create a workspace, add a user to it, then confirm the member appears in the roster.

ARAZZO

Anthropic Discover a Model and Send a Message

List available models, confirm a chosen model exists, then create a message with it.

ARAZZO

Anthropic Invite an Org Member and Confirm

Send an organization invite, then read it back and branch on whether it is still pending.

ARAZZO

Anthropic List Batches and Fetch Latest Results

List message batches, inspect the most recent one, and pull its results if it has ended.

ARAZZO

Anthropic Onboard an Org Member into a Workspace

Find an org member by email, create a workspace, and add that member to it.

ARAZZO

Anthropic Provision and Promote a Workspace Member

Create a workspace, add a member as a developer, then promote them to workspace admin.

ARAZZO

Anthropic Upload, List, and Clean Up a File

Upload a file, confirm it appears in the file list, then delete it to clean up.

ARAZZO

Anthropic Upload, Verify, and Download a File

Upload a file, read back its metadata, and download its content when it is downloadable.

ARAZZO

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GraphQL 1

GraphQL schemas published by this provider.

Anthropic GraphQL Schema

This GraphQL schema is a conceptual representation of the Anthropic Claude API derived from the REST API surface. The Anthropic API provides access to Claude large language mode...

GRAPHQL

Pricing Plans 1

Published pricing tiers and plan structures.

Anthropic Plans Pricing

5 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Anthropic Rate Limits

12 limits

RATE LIMITS

FinOps 1

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

Anthropic Finops

FINOPS

Features 26

Notable capabilities this provider offers.

Claude Opus 4.7 — most capable generally available model for complex reasoning and agentic coding

Claude Sonnet 4.6 — balanced model combining speed and intelligence with 1M context window

Claude Haiku 4.5 — fastest model with near-frontier intelligence

Messages API with text, vision, tool use, extended thinking, streaming, structured outputs

Prompt caching with automatic and manual breakpoints, 5-minute and 1-hour TTLs, cache reads at 10% of input price

Server-side compaction API for effectively infinite conversations on Opus 4.6/4.7 and Sonnet 4.6

Memory tool (client-side) for cross-conversation persistence with ZDR support

Message Batches API with 50% discount on both input and output tokens

Files API for upload-once / reuse-many content across Messages and Managed Agents

Agent Skills API (beta) — packaged domain expertise with progressive disclosure

Claude Managed Agents (beta) — Agents, Sessions, Environments with SSE streaming and managed sandboxes

Web Search tool ($10/1,000 searches) and Web Fetch tool (free)

Code Execution tool — Python + Bash + filesystem in sandbox; 1,550 free container-hours/month

Computer Use tool for browser and desktop automation (beta)

Advisor tool (beta) for pairing executor and high-intelligence advisor models

Tool Search tool and Programmatic Tool Calling

Token-bucket rate limiting with cache-aware ITPM (cache reads excluded on most models)

Five usage tiers (Tier 1-4 plus Monthly Invoicing) with automatic advancement

Usage & Cost Admin API and Claude Code Analytics Admin API for FinOps reporting

Rate Limits API for programmatic limit inspection

Workload Identity Federation for short-lived bearer tokens

Data residency controls (US-only inference at 1.1x pricing for models after Feb 2026)

Available via Claude API, Claude Platform on AWS, Microsoft Foundry, AWS Bedrock, and Google Vertex AI

{"Official SDKs" => "Python, TypeScript, Java, Go, Ruby, C#, PHP plus the `ant` CLI"}

Claude Code (terminal agent) and Claude Code GitHub Action

Open MCP specification stewardship via modelcontextprotocol.io

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Event Specifications 2

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Anthropic Messages Streaming API

AsyncAPI specification modeling the Server-Sent Events (SSE) stream produced by Anthropic's Messages API when `"stream": true` is set on a POST to `/v1/messages`. Transport: HTT...

ASYNCAPI