Matter website screenshot

Matter

Matter is a modern read-later application for people who take reading seriously — save articles, newsletters, podcasts, PDFs, and tweets from anywhere and read them in a clean, focused interface on iOS and the web, with highlighting, notes, tags, offline search, text-to-speech, and audio transcription of podcasts and videos. For Matter Pro subscribers, Matter ships a public REST API (api.getmatter.com/public/v1) to save, organize, search, and incrementally sync a reading library, secured with a personal Bearer token. It is complemented by a first-party CLI/TUI and official Obsidian, Roam, and Logseq highlight-export integrations. Matter is backed by GV (Google Ventures).

Matter publishes 6 APIs on the APIs.io network, including Account API, Annotations API, Items API, and 3 more. Tagged areas include Company, Consumer, Reading, Read Later, and Productivity.

Matter’s developer surface includes documentation, API reference, getting-started guide, authentication, CLI, support, signup flow, and 24 more developer resources.

🌐 Visit website 📡 Source on GitHub
50.3/100 developing ▬ flat Agent 31/100 agent ready saas Full breakdown ↓
scored 2026-09-06 · rubric v0.19.0
1 APIs
CompanyConsumerReadingRead LaterProductivityContentHighlightsBookmarking

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-09-06 · rubric v0.19.0
Composite quality — 50.3/100 · developing
Contract Quality 15.7 / 25
Developer Ergonomics 12.7 / 20
Access Clarity 6.8 / 20
Operational Transparency 6.8 / 13
Contract Governance 0.5 / 12
Discoverability 7.6 / 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 8 / 8
Request/Response Examples 7 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 0 / 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
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/matter: 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 6

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

Matter Account API

Your user profile and API quota.

Matter Annotations API

Highlights and notes on items.

Matter Items API

Articles, podcasts, videos, PDFs, and tweets in your library.

Matter Reading Sessions API

Reading time history.

Matter Search API

Full-text search across Matter.

Matter Tags API

Labels for organizing items.

Open Collections 7

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

API Collection

OPEN COLLECTION

Matter Account API

OPEN COLLECTION

Matter Account Annotations API

OPEN COLLECTION

Matter Account Items API

OPEN COLLECTION

Matter Account Reading Sessions API

OPEN COLLECTION

Matter Account Search API

OPEN COLLECTION

Matter Account Tags API

OPEN COLLECTION

Scroll for all 7

Rate Limits 1

Documented rate limits and quota policies.

Matter Rate Limits

6 limits

RATE LIMITS

Security Posture 3

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

Matter Authentication

http · 1 scheme

SECURITY

Matter Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Matter Vulnerability Disclosure

security.txt · contact published

SECURITY

Agentic Access 1

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

Matter Agentic Access

17 operations · 9 acting

17 operations · 9 acting

AGENTIC

Resources

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal
DeveloperPortal
 GettingStarted
GettingStarted
 SignUp
SignUp
 Login
Login

Documentation 2

Reference material describing how the API behaves

Documentation
Documentation
 APIReference
APIReference

Agent Surfaces 5

MCP servers, agent skills, and machine-readable catalogs

X-MCPServerCandidate
X-MCPServerCandidate
 AgentSkill
AgentSkill
 AgenticAccess
AgenticAccess
 LLMsTxt
LLMsTxt
 WellKnown
WellKnown

Design & Contract 5

Pagination, idempotency, versioning, errors, and events

Conventions
Conventions
 ErrorCatalog
ErrorCatalog
 Lifecycle
Lifecycle
 DataModel
DataModel
 Conformance
Conformance

Build 3

SDKs, sample code, and the tooling you integrate with

Packages
Packages
 CLI
CLI
 GitHubOrganization
GitHubOrganization

Access & Security 5

Authentication, authorization, and security posture

Authentication
Authentication
 SecurityTxt
SecurityTxt
 VulnerabilityDisclosure
VulnerabilityDisclosure
 Security
Security
 DomainSecurity
DomainSecurity

Operate 3

Status, limits, changes, and where to get help

RateLimits
RateLimits
 Deprecation
Deprecation
 Support
Support

Commercial 2

Pricing, plans, and the legal terms of use

TermsOfService
TermsOfService
 PrivacyPolicy
PrivacyPolicy

Company 1

The organization behind the API

Website
Website

Other 1

Properties that don't map to a standard resource type

Overlay
Overlay

Source (apis.yml)

apis.yml Raw ↑ 
aid: matter
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: high
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source:
  - authentication
  - rate-limits
  - security
  generated: '2026-09-03'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/matter.png
name: Matter
description: Matter is a modern read-later application for people who take reading seriously — save articles, newsletters,
  podcasts, PDFs, and tweets from anywhere and read them in a clean, focused interface on iOS and the web, with highlighting,
  notes, tags, offline search, text-to-speech, and audio transcription of podcasts and videos. For Matter Pro subscribers,
  Matter ships a public REST API (api.getmatter.com/public/v1) to save, organize, search, and incrementally sync a reading
  library, secured with a personal Bearer token. It is complemented by a first-party CLI/TUI and official Obsidian, Roam,
  and Logseq highlight-export integrations. Matter is backed by GV (Google Ventures).
url: https://raw.githubusercontent.com/api-evangelist/matter/refs/heads/main/apis.yml
x-type: company
x-source: vc-portfolio
x-backed-by:
- gv
x-tier: profiled
x-tier-reason: enriched-2026-07-20
specificationVersion: '0.23'
created: '2026-07-17'
modified: '2026-07-20'
x-enrichment:
  date: '2026-07-20'
  status: enriched
  artifacts_added: 22
  pass: local-v1
tags:
- Company
- Consumer
- Reading
- Read Later
- Productivity
- Content
- Highlights
- Bookmarking
apis:
- aid: matter:matter-account-api
  name: Matter Account API
  description: Your user profile and API quota.
  humanURL: https://docs.getmatter.com/api
  baseURL: https://api.getmatter.com/public/v1
  tags:
  - Account
  properties:
  - type: OpenAPI
    url: openapi/matter-account-api-openapi.yml
  - type: Documentation
    url: https://docs.getmatter.com/api
  - type: APIReference
    url: https://docs.getmatter.com/api
  - type: Authentication
    url: https://docs.getmatter.com/api/authentication
- aid: matter:matter-annotations-api
  name: Matter Annotations API
  description: Highlights and notes on items.
  humanURL: https://docs.getmatter.com/api
  baseURL: https://api.getmatter.com/public/v1
  tags:
  - Annotations
  properties:
  - type: OpenAPI
    url: openapi/matter-annotations-api-openapi.yml
  - type: Documentation
    url: https://docs.getmatter.com/api
  - type: APIReference
    url: https://docs.getmatter.com/api
  - type: Authentication
    url: https://docs.getmatter.com/api/authentication
- aid: matter:matter-items-api
  name: Matter Items API
  description: Articles, podcasts, videos, PDFs, and tweets in your library.
  humanURL: https://docs.getmatter.com/api
  baseURL: https://api.getmatter.com/public/v1
  tags:
  - Item
  tags_raw:
  - Items
  properties:
  - type: OpenAPI
    url: openapi/matter-items-api-openapi.yml
  - type: Documentation
    url: https://docs.getmatter.com/api
  - type: APIReference
    url: https://docs.getmatter.com/api
  - type: Authentication
    url: https://docs.getmatter.com/api/authentication
- aid: matter:matter-reading-sessions-api
  name: Matter Reading Sessions API
  description: Reading time history.
  humanURL: https://docs.getmatter.com/api
  baseURL: https://api.getmatter.com/public/v1
  tags:
  - Reading Sessions
  properties:
  - type: OpenAPI
    url: openapi/matter-reading-sessions-api-openapi.yml
  - type: Documentation
    url: https://docs.getmatter.com/api
  - type: APIReference
    url: https://docs.getmatter.com/api
  - type: Authentication
    url: https://docs.getmatter.com/api/authentication
- aid: matter:matter-search-api
  name: Matter Search API
  description: Full-text search across Matter.
  humanURL: https://docs.getmatter.com/api
  baseURL: https://api.getmatter.com/public/v1
  tags:
  - Search
  properties:
  - type: OpenAPI
    url: openapi/matter-search-api-openapi.yml
  - type: Documentation
    url: https://docs.getmatter.com/api
  - type: APIReference
    url: https://docs.getmatter.com/api
  - type: Authentication
    url: https://docs.getmatter.com/api/authentication
- aid: matter:matter-tags-api
  name: Matter Tags API
  description: Labels for organizing items.
  humanURL: https://docs.getmatter.com/api
  baseURL: https://api.getmatter.com/public/v1
  tags:
  - Tags
  properties:
  - type: OpenAPI
    url: openapi/matter-tags-api-openapi.yml
  - type: Documentation
    url: https://docs.getmatter.com/api
  - type: APIReference
    url: https://docs.getmatter.com/api
  - type: Authentication
    url: https://docs.getmatter.com/api/authentication
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
- FN: APIs.json
  email: info@apis.io
common:
- type: Overlay
  url: overlays/matter-openapi-overlay.yaml
- type: DeveloperPortal
  url: https://docs.getmatter.com
- type: Documentation
  url: https://docs.getmatter.com/api
- type: APIReference
  url: https://docs.getmatter.com/api
- type: GettingStarted
  url: https://docs.getmatter.com/api/quickstart
- type: Authentication
  url: authentication/matter-authentication.yml
- type: Conventions
  url: conventions/matter-conventions.yml
- type: ErrorCatalog
  url: errors/matter-problem-types.yml
- type: RateLimits
  url: rate-limits/matter-rate-limits.yml
- type: Lifecycle
  url: lifecycle/matter-lifecycle.yml
- type: Deprecation
  url: lifecycle/matter-lifecycle.yml
- type: DataModel
  url: data-model/matter-data-model.yml
- type: Conformance
  url: conformance/matter-conformance.yml
- type: Packages
  url: packages/matter-packages.yml
- type: CLI
  url: cli/matter-cli.yml
- type: X-MCPServerCandidate
  url: mcp/matter-mcp.yml
  note: 'Renamed from MCPServer 2026-09-03 (roadmap#247): the manifest self-describes as status: candidate — a tool list derived
    from the published API contracts, not an existing server. The scorer already read the manifest and reported mcp_server
    correctly; the MCPServer type was crediting the artifact-type surfaces with a server that does not exist.'
- type: AgentSkill
  url: skills/_index.yml
- type: AgenticAccess
  url: agentic-access/matter-agentic-access.yml
- type: LLMsTxt
  url: llms/matter-llms.txt
- type: WellKnown
  url: well-known/matter-well-known.yml
- type: SecurityTxt
  url: well-known/matter-security.txt
- type: VulnerabilityDisclosure
  url: security/matter-vulnerability-disclosure.yml
- type: Security
  url: security/matter-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/matter-domain-security.yml
- type: GitHubOrganization
  url: https://github.com/getmatterapp
- type: Support
  url: mailto:hello@getmatter.com
- type: SignUp
  url: https://web.getmatter.com
- type: Login
  url: https://web.getmatter.com
- type: TermsOfService
  url: https://www.getmatter.com/terms
- type: PrivacyPolicy
  url: https://www.getmatter.com/privacy
- type: Website
  url: https://www.getmatter.com

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