RealWorldAPIs

RealWorldAPIs MCP

RealWorldAPIs is an evidence-first API registry for AI agents connecting to the physical world.

A real-world API connects software or AI agents to data, devices, infrastructure or services representing the physical world — including weather, maps, mobility, logistics, IoT, energy and robotics.

This repository documents and provides a publicly inspectable MCP interface implementation for RealWorldAPIs.

The live hosted RealWorldAPIs service is the source of truth for current tools, schemas, recommendation behavior and evidence semantics. The hosted service may evolve independently from the code visible in this repository.

One core evidence rule applies throughout the service:

Unknown remains Unknown and is never treated as confirmed support.

Public interface, proprietary intelligence

RealWorldAPIs intentionally separates its public interoperability surface from its proprietary decision systems.

Public / interoperability surface

The following are intended to be publicly discoverable and usable for interoperability:

• the remote MCP endpoint and tool schemas
• public HTTP endpoints and OpenAPI descriptions
• public API catalog and capability/evidence outputs
• public documentation and usage examples
• factual provider metadata and evidence links
• structured recommendation and verification results returned by the hosted service

Proprietary hosted systems

The following are not published or licensed through this repository:

• the canonical RealWorldAPIs recommendation and ranking engine
• natural-language task parsing and task-frame logic
• capability retrieval, fusion and sibling-capability reranking logic
• internal scoring rules, weights and optimization logic
• verification and evidence-processing implementation
• assertion-generation and research pipelines
• benchmark tooling, active private evaluation sets and holdout sets
• internal administration, proposal and approval systems

The MCP layer calls hosted canonical RealWorldAPIs services for recommendation and evidence-backed decision support. Publishing an interface, schema or result does not publish the underlying hosted implementation.

See PROPRIETARY_NOTICE.md for the repository rights notice.

Live service

• Website: https://realworldapis.com
• Remote MCP endpoint: https://mcp.realworldapis.com/mcp
• MCP health: https://mcp.realworldapis.com/health
• Catalog JSON: https://realworldapis.com/api/catalog.json
• Capabilities JSON: https://realworldapis.com/api/capabilities.json
• Requirement verification: https://realworldapis.com/api/verify-requirement
• Structured recommendation: https://realworldapis.com/api/recommend
• OpenAPI: https://realworldapis.com/openapi.json
• Full LLM catalog: https://realworldapis.com/llms-full.txt
• Research: https://realworldapis.com/research/state-of-agent-ready-apis-2026

No RealWorldAPIs API key is currently required to discover or call the public MCP tools.

MCP tools

The live RealWorldAPIs MCP service currently exposes six read-only tools:

The live tool set and schemas are authoritative. The source-visible implementation in this repository may lag the hosted service.

Which tool should I use?

find_api_for_task

Use when the user describes a goal rather than a specific API.

Example task:

{  "task": "I need my agent to connect to a car and predict weather on the route"}

The structured shortlist returned by the canonical hosted recommender is the source of truth. Any AI comparison is constrained to that shortlist and is not permitted to introduce outside APIs.

search_apis

Use when the task is explicit enough to filter the registry directly.

Example:

{  "categories": ["Geospatial"],  "agent_capabilities": ["locate"],  "mcp": "Yes",  "min_readiness": 60,  "limit": 10}

Only explicit stored values are used. For example, mcp: "Yes" must not be satisfied by an API whose MCP status is Unknown.

search_capabilities

Use when the task is better expressed as an exact capability or execution requirement than as a broad API category.

Capability results can include execution, access, approval, hardware, sandbox, physical-consequence and reversibility fields when available from the canonical evidence graph.

verify_requirement

Use when you need to adjudicate one API against one exact requirement.

Example:

{  "api": "here-location-services",  "requirement": "truck routing in Sweden"}

The verifier returns an evidence-backed YES, NO, PARTIAL or UNKNOWN result. Unknown is never silently promoted into support.

get_api

Example:

{  "identifier": "geoapify"}

The response is the canonical RealWorldAPIs decision profile, including provider metadata, capabilities, authentication, protocol status and evidence links.

compare_apis

Example:

{  "apis": ["Geoapify", "Google Maps Platform", "Mapbox"],  "fields": [    "category",    "capabilities",    "agent_capabilities",    "auth_methods",    "openapi",    "mcp",    "agent_readiness_score"  ]}

The comparison is deterministic. RealWorldAPIs does not infer missing support or silently replace Unknown with a guess.

Connect

Any MCP client that supports remote Streamable HTTP can connect to:

https://mcp.realworldapis.com/mcp

Example MCP configuration:

{  "mcpServers": {    "realworldapis": {      "url": "https://mcp.realworldapis.com/mcp"    }  }}

Codex-style TOML

[mcp_servers.realworldapis]url = "https://mcp.realworldapis.com/mcp"

Evidence model

RealWorldAPIs is designed around a normalized evidence layer rather than free-form API recommendations.

The canonical dataset tracks fields such as:

• provider and category
• verified task-level capabilities
• agent action primitives
• authentication methods
• OpenAPI
• MCP
• A2A
• x402
• llms.txt
• public documentation status
• authentication verification
• access and setup requirements
• approval requirements
• hardware dependencies
• sandbox availability
• physical consequence
• irreversibility
• direct evidence links

Grounding rules

1. The canonical structured dataset is the source of truth.
2. Unknown is distinct from No.
3. AI comparison may not introduce APIs outside the structured shortlist.
4. Search and comparison tools use canonical stored evidence.
5. Hard provider facts require the appropriate evidence quality under the hosted RealWorldAPIs evidence policy.
6. Provider documentation should be checked before production integration.

Why RealWorldAPIs exists

General API directories are useful for broad discovery, but AI agents increasingly need a normalized way to answer questions such as:

• Which exact API capability can perform this task?
• Which APIs can locate a vehicle and route a technician?
• Which weather APIs are both agent-actionable and machine-readable?
• Which robotics APIs expose machine-usable interfaces?
• Which APIs can be combined for a physical-world workflow?
• What access, approval, hardware or safety constraints apply?
• What evidence gaps remain before an agent should rely on a provider?

RealWorldAPIs focuses specifically on APIs that connect software and agents to the physical world.

Research and dataset

The public research page, State of Agent-Ready Real-World APIs 2026, summarizes the catalog snapshot across agent-readiness, protocol support and category-level evidence:

https://realworldapis.com/research/state-of-agent-ready-apis-2026

Machine-readable research data:

https://realworldapis.com/research/state-of-agent-ready-apis-2026.json

The public catalog is available at:

https://realworldapis.com/api/catalog.json

The verified capability graph is available at:

https://realworldapis.com/api/capabilities.json

Architecture

The MCP server is intentionally an interface layer over canonical hosted RealWorldAPIs services.

MCP client   |   +-- find_api_for_task --------> hosted canonical recommender   +-- verify_requirement --------> hosted evidence/verifier layer   +-- search_capabilities -------> canonical capability graph   +-- search_apis ---------------> canonical API catalog   +-- get_api -------------------> canonical API decision profile   +-- compare_apis --------------> canonical evidence fields

This avoids maintaining a second independent recommendation, ranking or evidence system inside the public MCP interface.

The implementation of the canonical hosted recommendation, ranking, verification and evidence-processing systems is proprietary and is not contained in this repository.

See docs/ARCHITECTURE.md for additional public interface details.

Repository layout

src/  worker.js               Publicly inspectable MCP interface implementation
examples/  requests.md             Example tool calls and expected semantics
docs/  ARCHITECTURE.md         Public data flow, grounding and failure behavior  DATA_MODEL.md           Important catalog fields and evidence semantics
CHANGELOG.md               Release historyCONTRIBUTING.md            Contribution and correction workflowPROPRIETARY_NOTICE.md      Repository rights and proprietary-service boundary

Status

The hosted RealWorldAPIs service evolves independently from this public repository.

For current production behavior, use the live MCP endpoint and canonical website endpoints. Third-party directories and this repository may temporarily show an older tool count, description, implementation detail or schema after a production deployment.

Contributing

Corrections to public API metadata are welcome when supported by current provider documentation. Please include the evidence URL and identify the exact field that should change.

Public contributions do not grant access to, or imply publication of, proprietary RealWorldAPIs ranking, verification, optimization, benchmark or research systems.

See CONTRIBUTING.md.

Rights and licensing

This repository is publicly source-visible but is not released under an open-source license.

No MIT, Apache, BSD, GPL or other open-source license is granted by this repository.

Use of the hosted RealWorldAPIs service is separate from rights in repository source code. Public protocol descriptions, schemas and factual outputs may be used for interoperability as permitted by applicable terms and law, but the proprietary hosted RealWorldAPIs systems are not licensed through this repository.

See PROPRIETARY_NOTICE.md.

Copyright © 2026 RealWorldAPIs. All rights reserved.