Space Frontiers

Space Frontiers is a Wyoming corporation whose search and AI product, Machine Library (formerly Space Frontiers search, moved to machinelibrary.ai on 2026-09-12), is a full-text retrieval API and hosted MCP server over a corpus the provider describes as multi-billion documents: peer-reviewed papers (CrossRef, PubMed, arXiv), books, USPTO patents, Wikipedia, technical standards, YouTube transcripts, and live Reddit, Telegram and Discord posts. It is built for AI agents doing literature review, fact-checking, citation walking and grounded research synthesis, returning compact reranked hits with canonical source URIs (DOI, arXiv, PMID, ISBN) and token-bounded full text. Three surfaces share one account and API key: a REST API at api.machinelibrary.ai (OpenAPI 3.1, pay-as-you-go), a Streamable-HTTP MCP server at mcp.machinelibrary.ai (OAuth 2.1 with PKCE and RFC 7591 dynamic registration against the issuer api.machinelibrary.ai, scope search, or a Bearer API key), and an A2A agent at machinelibrary.ai/a2a. It also ships a PDF/EPUB/DJVU-to-Markdown recognition API and Stripe-settled prepaid credit packages for agents (ACP checkout, MPP top-up). The company also publishes Hermes, an open-source Rust search engine with a gRPC contract and Python/TypeScript clients.

Space Frontiers publishes 9 API contracts indexed on the APIs.io network, including Documents API, Payments API, Raw document downloads API, and 6 more. Tagged areas include Research, Scholarly Search, Full-Text Search, Retrieval, and RAG.

The Space Frontiers catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

Space Frontiers’ developer surface includes changelog, documentation, API reference, getting-started guide, pricing, support, signup flow, and 44 more developer resources.

65.5/100 strong ▬ flat Agent 66/100 agent ready Front door AI 5/6 prominent saas Full breakdown ↓
scored 2026-10-09 · rubric v0.23.0
4 published contracts 1 MCP Servers
ResearchScholarly SearchFull-Text SearchRetrievalRAGPatentsDocumentsOCRDocument RecognitionMCPA2AAgent-NativeAI AgentsDataSearch

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-10-09 · rubric v0.23.0
Regulatory Posture applies to this provider. Its tags matched the Education & Research 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/.
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/machinelibrary-ai: 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 9

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

Machine Library MCP Server

Hosted Streamable-HTTP MCP server at https://mcp.machinelibrary.ai (legacy https://mcp.spacefrontiers.org still served) exposing nine machinelibrary_* tools: four read-only, ide...

Machine Library A2A Agent

A2A (protocolVersion 0.3.0) research and commerce agent at https://machinelibrary.ai/a2a over JSON-RPC: grounded research answers with citation artifacts, search-access guidance...

Hermes Search Engine gRPC API

Self-hosted, MIT-licensed Rust search engine published by Space Frontiers (github.com/SpaceFrontiers/hermes) with a published protobuf wire contract: hermes.SearchService (Searc...

Space Frontiers Documents API

Fetch documents by ID or canonical URI.

Space Frontiers Payments API

The Payments API from Space Frontiers — 1 operation(s) for payments.

Space Frontiers Raw document downloads API

Authenticated, feature-gated streaming of PDF, EPUB, and DJVU library originals.

Space Frontiers Recognition API

Document recognition: PDF, EPUB, and DJVU to structured Markdown with quality reports.

Space Frontiers Search API

Ranked retrieval and document similarity.

Space Frontiers Conversations API

Retrieval-augmented conversation workflows.

Scroll for all 9

MCP Servers 1

Model Context Protocol servers that expose these APIs to AI agents.

Space Frontiers MCP Server

Remote MCP server at mcp.machinelibrary.ai over streamable HTTP requiring OAuth; 9 tools listed.

MCP SERVER

Pricing Plans 1

Published pricing tiers and plan structures.

Rate Limits 1

Documented rate limits and quota policies.

Machinelibrary Ai Rate Limits

5 limits

RATE LIMITS

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Machinelibrary Ai Context

59 classes · 202 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Space Frontiers API Rules

16 rules · 9 errors 5 warnings 2 info

SPECTRAL

OpenAPI Overlays 1

Overlays applied on top of this provider's contracts. Each card says who wrote it: a document the provider publishes, or one API Evangelist derived or generated.

Machinelibrary Ai Openapi Overlay

7 actions · update · machinelibrary-ai-openapi.yml

GENERATED

JSON Schema 12

Standalone JSON Schema definitions for this provider's data models.

AgentCommentSubmission

9 properties

JSON SCHEMA

ByUriResponse

0 properties

JSON SCHEMA

ConversationRequest

11 properties

JSON SCHEMA

ConversationResponse

10 properties

JSON SCHEMA

FeedbackAccepted

2 properties

JSON SCHEMA

RecognitionJobStatus

11 properties

JSON SCHEMA

RecognitionSubmission

3 properties

JSON SCHEMA

SearchFeedback

6 properties

JSON SCHEMA

SearchRequestV2

36 properties

JSON SCHEMA

SimilarRequestV2

4 properties

JSON SCHEMA

V2DocumentResponse

3 properties

JSON SCHEMA

V2SearchResponse

10 properties

JSON SCHEMA

Scroll for all 12

Security Posture 3

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

Machinelibrary Ai Authentication

apiKey/http/oauth2 · 3 schemes

SECURITY

Machinelibrary Ai Domain Security

TLSv1.3 · HSTS · DNSSEC · DMARC

SECURITY

Machinelibrary Ai Vulnerability Disclosure

security.txt · contact published

SECURITY

Scopes 1

OAuth scopes governing access to this provider's APIs.

Machinelibrary Ai Scopes

1 scope

1 scopes

SCOPES

Agentic Access 1

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

Machinelibrary Ai Agentic Access

42 operations · 18 acting

42 operations · 18 acting

AGENTIC

Resources

Get Started 3

Portal, sign-up, and the first successful call

Documentation 3

Reference material describing how the API behaves

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

Design & Contract 9

Pagination, idempotency, versioning, errors, and events

Scroll for all 9

Build 4

SDKs, sample code, and the tooling you integrate with

Access & Security 6

Authentication, authorization, and security posture

Operate 5

Status, limits, changes, and where to get help

Commercial 4

Pricing, plans, and the legal terms of use

Company 3

The organization behind the API

Other 9

Properties that don't map to a standard resource type

Scroll for all 9

Source (apis.yml)

apis.yml Raw ↑
aid: machinelibrary-ai
name: Space Frontiers
description: 'Space Frontiers is a Wyoming corporation whose search and AI product, Machine Library (formerly Space Frontiers
  search, moved to machinelibrary.ai on 2026-09-12), is a full-text retrieval API and hosted MCP server over a corpus the
  provider describes as multi-billion documents: peer-reviewed papers (CrossRef, PubMed, arXiv), books, USPTO patents, Wikipedia,
  technical standards, YouTube transcripts, and live Reddit, Telegram and Discord posts. It is built for AI agents doing literature
  review, fact-checking, citation walking and grounded research synthesis, returning compact reranked hits with canonical
  source URIs (DOI, arXiv, PMID, ISBN) and token-bounded full text. Three surfaces share one account and API key: a REST API
  at api.machinelibrary.ai (OpenAPI 3.1, pay-as-you-go), a Streamable-HTTP MCP server at mcp.machinelibrary.ai (OAuth 2.1
  with PKCE and RFC 7591 dynamic registration against the issuer api.machinelibrary.ai, scope search, or a Bearer API key),
  and an A2A agent at machinelibrary.ai/a2a. It also ships a PDF/EPUB/DJVU-to-Markdown recognition API and Stripe-settled
  prepaid credit packages for agents (ACP checkout, MPP top-up). The company also publishes Hermes, an open-source Rust search
  engine with a gRPC contract and Python/TypeScript clients.'
url: https://raw.githubusercontent.com/api-evangelist/machinelibrary-ai/refs/heads/main/apis.yml
deliveryModel:
  model: saas
  license_evidence:
    not_product:
    - spacefrontiers/hermes
    - spacefrontiers/mcp
  open_source: unknown
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: low
  source:
  - openapi
  - pricing
  - repository-not-product
  generated: '2026-09-25'
  method: derived
image: https://machinelibrary.ai/press/icon-512.png
x-type: company
x-source: harvest:a2a-registry
x-tier: profiled
x-tier-reason: enrichment pipeline local-v3 pass on 2026-09-19 found a live OpenAPI 3.1, hosted MCP server, A2A agent card,
  llms.txt, RFC 8414/9728 metadata and an RFC 9727 api-catalog
website: https://machinelibrary.ai
x-legal-name: Space Frontiers
x-headquarters: Sheridan, Wyoming, United States
x-product-name: Machine Library
x-former-domain: spacefrontiers.org
specificationVersion: '0.20'
created: '2026-09-19'
modified: '2026-10-06'
tags:
- Research
- Scholarly Search
- Full-Text Search
- Retrieval
- RAG
- Patents
- Documents
- OCR
- Document Recognition
- MCP
- A2A
- Agent-Native
- AI Agents
- Data
- Search
tags_raw:
- research
- scholarly-search
- full-text-search
- retrieval
- rag
- patents
- documents
- ocr
- document-recognition
- mcp
- a2a
- agent-native
- ai-agents
- data
- search
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- url: https://machinelibrary.ai/api/search/rss
  type: BlogRSS
- type: AgenticAccess
  url: agentic-access/machinelibrary-ai-agentic-access.yml
- type: Spectral
  url: rules/machinelibrary-ai-rules.yml
- type: JSONLD
  url: json-ld/machinelibrary-ai-context.jsonld
- type: Vocabulary
  url: vocabulary/machinelibrary-ai-vocabulary.yml
- type: Security
  url: security/machinelibrary-ai-vulnerability-disclosure.yml
- type: Hosts
  url: hosts/machinelibrary-ai-hosts.yml
- type: Vendors
  url: vendors/machinelibrary-ai-vendors.yml
- type: StatusPage
  url: https://machinelibrary.ai/status
- type: Operations
  url: https://machinelibrary.ai/docs/api/operations
- type: ChangeLog
  url: https://machinelibrary.ai/changelog
- type: Datasets
  url: https://machinelibrary.ai/datasets
- type: SecurityTxt
  url: https://machinelibrary.ai/.well-known/security.txt
- type: APICatalog
  url: https://machinelibrary.ai/.well-known/api-catalog
- type: OpenAPI
  url: https://machinelibrary.ai/docs/openapi.json
- type: VulnerabilityDisclosure
  url: security/machinelibrary-ai-vulnerability-disclosure.yml
- type: Overlay
  url: overlays/machinelibrary-ai-openapi-overlay.yaml
- type: Website
  url: https://machinelibrary.ai/
- type: Documentation
  url: https://machinelibrary.ai/docs/api
- type: APIReference
  url: https://machinelibrary.ai/docs/api/reference
- type: GettingStarted
  url: https://machinelibrary.ai/docs/api
- type: Pricing
  url: https://machinelibrary.ai/pricing
- type: Support
  url: https://machinelibrary.ai/contacts
- type: Newsroom
  url: https://machinelibrary.ai/press
- type: GitHubOrganization
  url: https://github.com/SpaceFrontiers
- type: SignUp
  url: https://machinelibrary.ai/auth/signup
- type: Login
  url: https://machinelibrary.ai/auth/signin
- type: TermsOfService
  url: https://machinelibrary.ai/terms-of-service
- type: PrivacyPolicy
  url: https://machinelibrary.ai/privacy
- type: LLMsTxt
  url: llms/machinelibrary-ai-llms.txt
- type: MCPServer
  url: mcp/machinelibrary-ai-mcp.yml
- type: ToolCrosswalk
  url: mcp/machinelibrary-ai-tool-crosswalk.yml
- type: AgentCard
  url: a2a/machinelibrary-ai-a2a.yml
- type: WellKnown
  url: well-known/machinelibrary-ai-well-known.yml
- type: Packages
  url: packages/machinelibrary-ai-packages.yml
- type: SDKs
  url: packages/machinelibrary-ai-packages.yml
- type: Conformance
  url: conformance/machinelibrary-ai-conformance.yml
- type: Authentication
  url: authentication/machinelibrary-ai-authentication.yml
- type: OAuthScopes
  url: scopes/machinelibrary-ai-scopes.yml
- type: Conventions
  url: conventions/machinelibrary-ai-conventions.yml
- type: Idempotency
  url: conventions/machinelibrary-ai-conventions.yml
- type: ErrorCatalog
  url: errors/machinelibrary-ai-problem-types.yml
- type: Lifecycle
  url: lifecycle/machinelibrary-ai-lifecycle.yml
- type: DomainSecurity
  url: security/machinelibrary-ai-domain-security.yml
- type: Plans
  url: plans/machinelibrary-ai-plans-pricing.yml
- type: RateLimits
  url: rate-limits/machinelibrary-ai-rate-limits.yml
- type: ChangeLog
  url: changelog/machinelibrary-ai-changelog.yml
- type: DataModel
  url: data-model/machinelibrary-ai-data-model.yml
- type: AgentSkill
  url: skills/_index.yml
- type: RegulatoryPosture
  url: regulatory/machinelibrary-ai-regulatory-posture.yml
- type: Protobuf
  url: grpc/machinelibrary-ai-hermes.proto
apis:
- name: Machine Library MCP Server
  description: 'Hosted Streamable-HTTP MCP server at https://mcp.machinelibrary.ai (legacy https://mcp.spacefrontiers.org
    still served) exposing nine machinelibrary_* tools: four read-only, idempotent retrieval tools (machinelibrary_search_documents,
    machinelibrary_search_social, machinelibrary_fetch_document, machinelibrary_search_in_document), machinelibrary_research
    for cited answers billed per turn, machinelibrary_search_feedback for relevance ratings, machinelibrary_comment_on_document
    and machinelibrary_vote_on_comment for AI-labeled public comments and votes on documents, and machinelibrary_top_up_balance
    for Stripe MPP credit purchases. The legacy spacefrontiers_* names remain accepted as aliases. OAuth 2.1 with PKCE S256
    and RFC 7591 dynamic client registration against the issuer https://api.machinelibrary.ai (scope search), or a Bearer
    API key; 60 requests per minute per source IP. Listed in the official MCP registry as io.github.SpaceFrontiers/mcp; the
    four retrieval tools are MIT-licensed on GitHub.'
  humanURL: https://machinelibrary.ai/mcp
  baseURL: https://mcp.machinelibrary.ai
  tags:
  - MCP
  - Agent-Native
  - Retrieval
  - Research
  tags_raw:
  - mcp
  - agent-native
  - retrieval
  - research
  properties:
  - type: MCPServer
    url: mcp/machinelibrary-ai-mcp.yml
  - type: ToolCrosswalk
    url: mcp/machinelibrary-ai-tool-crosswalk.yml
  - type: Documentation
    url: https://machinelibrary.ai/mcp
  - type: GettingStarted
    url: https://machinelibrary.ai/install.md
  - type: SourceCode
    url: https://github.com/SpaceFrontiers/mcp
  - type: MCPRegistry
    url: https://registry.modelcontextprotocol.io/v0/servers?search=spacefrontiers
  - type: MCPServerCard
    url: https://machinelibrary.ai/.well-known/mcp/server-card.json
  - type: RateLimits
    url: rate-limits/machinelibrary-ai-rate-limits.yml
  - type: OAuthScopes
    url: scopes/machinelibrary-ai-scopes.yml
  aid: machinelibrary-ai:machine-library-mcp-server
- name: Machine Library A2A Agent
  description: 'A2A (protocolVersion 0.3.0) research and commerce agent at https://machinelibrary.ai/a2a over JSON-RPC: grounded
    research answers with citation artifacts, search-access guidance, and prepaid-credit sales settled through Stripe (ACP
    checkout sessions and MPP payment challenges), with two AP2 merchant-role extensions declared. The agent card is served
    at /.well-known/agent-card.json on machinelibrary.ai and spacefrontiers.org. Unauthenticated message/send is answered
    live with authentication guidance.'
  humanURL: https://machinelibrary.ai/.well-known/agent-card.json
  baseURL: https://machinelibrary.ai/a2a
  x-baseurl-note: JSON-RPC endpoint; answers POST message/send (200) and 404s a plain GET, so the humanURL is the served agent
    card rather than the endpoint.
  tags:
  - A2A
  - Agent-Native
  - Research
  - Payments
  tags_raw:
  - a2a
  - agent-native
  - research
  - payments
  properties:
  - type: AgentCard
    url: a2a/machinelibrary-ai-a2a.yml
  - type: Documentation
    url: https://api.machinelibrary.ai/auth.md
  aid: machinelibrary-ai:machine-library-a2a-agent
- name: Hermes Search Engine gRPC API
  description: 'Self-hosted, MIT-licensed Rust search engine published by Space Frontiers (github.com/SpaceFrontiers/hermes)
    with a published protobuf wire contract: hermes.SearchService (Search, GetDocument, GetIndexInfo, GetTextStats) and hermes.IndexService
    (index creation, streaming ingestion, primary-key deletion and upsert, commit, merge, vector-index retraining), plus hermes.broker.BrokerService
    for shard topology. Distributed as crates (hermes-core, hermes-server, hermes-broker, hermes-tool), PyPI (hermes-client-python),
    npm (hermes-client-typescript, hermes-wasm). There is no hosted endpoint: you run hermes-server yourself.'
  humanURL: https://github.com/SpaceFrontiers/hermes
  x-deployment: self-hosted
  x-no-hosted-base-url: The gRPC server is run by the consumer (cargo install hermes-server); Space Frontiers publishes no
    hosted Hermes endpoint, so no baseURL is recorded rather than inventing one.
  tags:
  - Search
  - gRPC
  - Open Source
  tags_raw:
  - search
  - grpc
  - open-source
  - Open Source
  - Open-Source
  properties:
  - type: Protobuf
    url: grpc/machinelibrary-ai-hermes.proto
  - type: Protobuf
    url: grpc/machinelibrary-ai-hermes-broker.proto
  - type: Documentation
    url: https://github.com/SpaceFrontiers/hermes/blob/main/hermes-proto/README.md
  - type: SourceCode
    url: https://github.com/SpaceFrontiers/hermes
  aid: machinelibrary-ai:hermes-search-engine-grpc-api
- aid: machinelibrary-ai:machinelibrary-ai-documents-api
  name: Space Frontiers Documents API
  description: Fetch documents by ID or canonical URI.
  humanURL: https://machinelibrary.ai/docs/api
  baseURL: https://api.machinelibrary.ai
  tags:
  - Documents
  properties:
  - type: OpenAPI
    url: openapi/machinelibrary-ai-documents-api-openapi.yml
  - type: Documentation
    url: https://machinelibrary.ai/docs/api
  - type: APIReference
    url: https://machinelibrary.ai/docs/api/reference
  - type: Authentication
    url: authentication/machinelibrary-ai-authentication.yml
  - type: OAuthScopes
    url: scopes/machinelibrary-ai-scopes.yml
  - type: Conventions
    url: conventions/machinelibrary-ai-conventions.yml
  - type: Idempotency
    url: conventions/machinelibrary-ai-conventions.yml
  - type: ErrorCatalog
    url: errors/machinelibrary-ai-problem-types.yml
  - type: DataModel
    url: data-model/machinelibrary-ai-data-model.yml
  - type: RateLimits
    url: rate-limits/machinelibrary-ai-rate-limits.yml
  - type: Plans
    url: plans/machinelibrary-ai-plans-pricing.yml
  - type: Pricing
    url: https://api.machinelibrary.ai/v1/pricing
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-by-uri-response-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-v2-document-response-schema.json
- aid: machinelibrary-ai:machinelibrary-ai-payments-api
  name: Space Frontiers Payments API
  description: The Payments API from Space Frontiers — 1 operation(s) for payments.
  humanURL: https://machinelibrary.ai/docs/api
  baseURL: https://api.machinelibrary.ai
  tags:
  - Payments
  properties:
  - type: OpenAPI
    url: openapi/machinelibrary-ai-payments-api-openapi.yml
  - type: Documentation
    url: https://machinelibrary.ai/docs/api
  - type: APIReference
    url: https://machinelibrary.ai/docs/api/reference
  - type: Authentication
    url: authentication/machinelibrary-ai-authentication.yml
  - type: OAuthScopes
    url: scopes/machinelibrary-ai-scopes.yml
  - type: Conventions
    url: conventions/machinelibrary-ai-conventions.yml
  - type: Idempotency
    url: conventions/machinelibrary-ai-conventions.yml
  - type: ErrorCatalog
    url: errors/machinelibrary-ai-problem-types.yml
  - type: DataModel
    url: data-model/machinelibrary-ai-data-model.yml
  - type: RateLimits
    url: rate-limits/machinelibrary-ai-rate-limits.yml
  - type: Plans
    url: plans/machinelibrary-ai-plans-pricing.yml
  - type: Pricing
    url: https://api.machinelibrary.ai/v1/pricing
- aid: machinelibrary-ai:machinelibrary-ai-raw-document-downloads-api
  name: Space Frontiers Raw document downloads API
  description: Authenticated, feature-gated streaming of PDF, EPUB, and DJVU library originals.
  humanURL: https://machinelibrary.ai/docs/api
  baseURL: https://api.machinelibrary.ai
  tags:
  - Raw document downloads
  properties:
  - type: OpenAPI
    url: openapi/machinelibrary-ai-raw-document-downloads-api-openapi.yml
  - type: Documentation
    url: https://machinelibrary.ai/docs/api
  - type: APIReference
    url: https://machinelibrary.ai/docs/api/reference
  - type: Authentication
    url: authentication/machinelibrary-ai-authentication.yml
  - type: OAuthScopes
    url: scopes/machinelibrary-ai-scopes.yml
  - type: Conventions
    url: conventions/machinelibrary-ai-conventions.yml
  - type: Idempotency
    url: conventions/machinelibrary-ai-conventions.yml
  - type: ErrorCatalog
    url: errors/machinelibrary-ai-problem-types.yml
  - type: DataModel
    url: data-model/machinelibrary-ai-data-model.yml
  - type: RateLimits
    url: rate-limits/machinelibrary-ai-rate-limits.yml
  - type: Plans
    url: plans/machinelibrary-ai-plans-pricing.yml
  - type: Pricing
    url: https://api.machinelibrary.ai/v1/pricing
- aid: machinelibrary-ai:machinelibrary-ai-recognition-api
  name: Space Frontiers Recognition API
  description: 'Document recognition: PDF, EPUB, and DJVU to structured Markdown with quality reports.'
  humanURL: https://machinelibrary.ai/docs/api
  baseURL: https://api.machinelibrary.ai
  tags:
  - Recognition
  properties:
  - type: OpenAPI
    url: openapi/machinelibrary-ai-recognition-api-openapi.yml
  - type: Documentation
    url: https://machinelibrary.ai/docs/api
  - type: APIReference
    url: https://machinelibrary.ai/docs/api/reference
  - type: Authentication
    url: authentication/machinelibrary-ai-authentication.yml
  - type: OAuthScopes
    url: scopes/machinelibrary-ai-scopes.yml
  - type: Conventions
    url: conventions/machinelibrary-ai-conventions.yml
  - type: Idempotency
    url: conventions/machinelibrary-ai-conventions.yml
  - type: ErrorCatalog
    url: errors/machinelibrary-ai-problem-types.yml
  - type: DataModel
    url: data-model/machinelibrary-ai-data-model.yml
  - type: RateLimits
    url: rate-limits/machinelibrary-ai-rate-limits.yml
  - type: Plans
    url: plans/machinelibrary-ai-plans-pricing.yml
  - type: Pricing
    url: https://api.machinelibrary.ai/v1/pricing
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-recognition-job-status-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-recognition-submission-schema.json
- aid: machinelibrary-ai:machinelibrary-ai-search-api
  name: Space Frontiers Search API
  description: Ranked retrieval and document similarity.
  humanURL: https://machinelibrary.ai/docs/api
  baseURL: https://api.machinelibrary.ai
  tags:
  - Search
  properties:
  - type: OpenAPI
    url: openapi/machinelibrary-ai-search-api-openapi.yml
  - type: Documentation
    url: https://machinelibrary.ai/docs/api
  - type: APIReference
    url: https://machinelibrary.ai/docs/api/reference
  - type: Authentication
    url: authentication/machinelibrary-ai-authentication.yml
  - type: OAuthScopes
    url: scopes/machinelibrary-ai-scopes.yml
  - type: Conventions
    url: conventions/machinelibrary-ai-conventions.yml
  - type: Idempotency
    url: conventions/machinelibrary-ai-conventions.yml
  - type: ErrorCatalog
    url: errors/machinelibrary-ai-problem-types.yml
  - type: DataModel
    url: data-model/machinelibrary-ai-data-model.yml
  - type: RateLimits
    url: rate-limits/machinelibrary-ai-rate-limits.yml
  - type: Plans
    url: plans/machinelibrary-ai-plans-pricing.yml
  - type: Pricing
    url: https://api.machinelibrary.ai/v1/pricing
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-search-request-v2-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-v2-search-response-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-similar-request-v2-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-search-feedback-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-feedback-accepted-schema.json
- aid: machinelibrary-ai:machinelibrary-ai-conversations-api
  name: Space Frontiers Conversations API
  description: Retrieval-augmented conversation workflows.
  humanURL: https://machinelibrary.ai/mcp
  baseURL: https://mcp.machinelibrary.ai
  tags:
  - Conversations
  properties:
  - type: OpenAPI
    url: openapi/machinelibrary-ai-conversations-api-openapi.yml
  - type: Documentation
    url: https://machinelibrary.ai/docs/api
  - type: APIReference
    url: https://machinelibrary.ai/docs/api/reference
  - type: Authentication
    url: authentication/machinelibrary-ai-authentication.yml
  - type: OAuthScopes
    url: scopes/machinelibrary-ai-scopes.yml
  - type: Conventions
    url: conventions/machinelibrary-ai-conventions.yml
  - type: Idempotency
    url: conventions/machinelibrary-ai-conventions.yml
  - type: ErrorCatalog
    url: errors/machinelibrary-ai-problem-types.yml
  - type: DataModel
    url: data-model/machinelibrary-ai-data-model.yml
  - type: RateLimits
    url: rate-limits/machinelibrary-ai-rate-limits.yml
  - type: Plans
    url: plans/machinelibrary-ai-plans-pricing.yml
  - type: Pricing
    url: https://api.machinelibrary.ai/v1/pricing
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-search-request-v2-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-conversation-response-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-conversation-request-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-v2-search-response-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-agent-comment-submission-schema.json
  - type: JSONSchema
    url: json-schema/machinelibrary-ai-recognition-job-status-schema.json
x-a2a:
  verified: true
  probed: '2026-09-26'
  url: https://machinelibrary.ai/.well-known/agent-card.json
  grade: conformant
  protocol_version: 0.3.0
  control: 404
x-correction-request:
  requested: '2026-09-28'
  source:
  - https://github.com/api-evangelist/machinelibrary-ai/pull/1
  request: 'Provider PR #1 (ppodolsky, 2026-09-26), verified live 2026-09-28; not merged because it predates the 09-27 per-area
    OpenAPI split. Its rate-limits file is committed (12/60/30 requests per minute per source IP; https://machinelibrary.ai/docs/api/operations#limits).
    Capture: OAuth authorization server issuer https://api.machinelibrary.ai, scopes_supported [search], PKCE S256, dynamic
    client registration at /v2/oauth/register, protected-resource metadata on mcp.machinelibrary.ai naming that issuer (legacy
    spacefrontiers hosts serve the same issuer); pages Operations https://machinelibrary.ai/docs/api/operations, ChangeLog
    https://machinelibrary.ai/changelog, StatusPage https://machinelibrary.ai/status, Datasets https://machinelibrary.ai/datasets;
    security.txt and api-catalog. MCP tools are renamed machinelibrary_* and number 9 in the live llms.txt (comment_on_document,
    vote_on_comment added); live OpenAPI https://machinelibrary.ai/docs/openapi.json has 21 paths. Note: their api-catalog
    links mcp.machinelibrary.ai/.well-known/mcp/server-card.json, which returns 404.'
  earlier:
    requested: '2026-09-27'
    source: https://github.com/api-search/inbox/issues/39
    request: 'Correction (with source-artifact PR https://github.com/api-evangelist/machinelibrary-ai/pull/1 -- review, do
      NOT merge wholesale): provider page links https://apis.io/servers/machinelibrary-ai/space-frontiers-mcp-server/ which
      404s -- use the current MCP product name so a working server page is generated; fix inconsistent counts and stale scope
      data. Re-profile from current sources.'
  applied: '2026-10-03'
  applied_note: 'Hand-applied after the local re-profile ignored this block; every fact re-probed live 2026-10-03. Applied:
    MCP manifest rebuilt with the nine machinelibrary_* tools and their descriptions from machinelibrary.ai/mcp and llms.txt
    (live tools/list answers 401 without credentials, so the four open-source tools carry tools/list output from the provider''s
    MIT server run in-process, the five hosted-only tools have no published input schema); legacy spacefrontiers_* aliases
    recorded; rate limits 12/12/60/30 plus 30 agent comments per day; OAuth issuer moved to https://api.machinelibrary.ai
    (scope search, PKCE S256, DCR /v2/oauth/register) in authentication, scopes and well-known; Operations, ChangeLog, StatusPage,
    Datasets, SecurityTxt, APICatalog and live OpenAPI pointers; security.txt (now 200) and refreshed well-known captures,
    llms.txt. Live OpenAPI has 21 paths; the committed six-area split already covers exactly those 21, so no re-pull. inbox#39:
    MCP API entry already named Machine Library MCP Server and the description now uses current tool names and counts; the
    corpus count is now the provider''s own ''multi-billion documents'' wording. The api-catalog no longer links the 404ing
    mcp-host server card (it links the apex copy, which resolves). Not applied: the apis.io server-page 404 is a site rebuild,
    not a repo fix.'
x-enrichment:
  date: '2026-09-28'
  status: enriched
  artifacts_added: 21
  pass: modular-v1
  engine: identity=local,contract=local,surfaces=local,docs=local,regulatory=local

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