Matrix Client-Server API
48
AI ReadinessNon-Ready (D+)48/100
Agent-ready OpenAPI document · curated by JenticCommunicationsChat Messagingbearer, apiKey32 EndpointsREST
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For Agents
Create and join Matrix rooms, send messages, manage room state, and sync user filters across any standards-compliant Matrix homeserver.
Use for: Create a new Matrix room called 'project-updates' with public join rules, I want to join the room with alias #room:matrix.org, Invite a user to a Matrix room by their MXID, Kick a user from a moderated room with a reason
Not supported: Does not handle homeserver administration, federation server-server traffic, or media repository operations - use for client-side room and user operations against an existing Matrix homeserver only.
Jentic publishes the only available OpenAPI specification for Matrix Client-Server API, keeping it validated and agent-ready. Matrix is an open standard for decentralised real-time communication, and the Client-Server API defines how a client talks to its homeserver to authenticate users, create and join rooms, send messages, and sync state. The spec covers core room operations (create, invite, join, leave, kick, ban), user filters, room aliases and visibility, and the messaging primitives that bridge clients across federated homeservers. It is intended for developers building Matrix clients, bridge bots, and AI agents that participate in Matrix rooms.
Install Jentic One Beta
Connect the Matrix Client-Server API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Matrix Client-Server API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
1
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fmatrix.org%2Fmatrix" | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fmatrix.org%2Fmatrix" | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
Capabilities
What an agent can do with Matrix Client-Server API.
Create new Matrix rooms with configurable visibility and join rules
Join, leave, invite, kick, and ban users from a room
Manage room aliases under a homeserver's alias namespace
Define and reuse user filters that scope sync responses
Update a room's join visibility in the published room directory
Send and receive room messages via the standard Matrix events model
Use Cases
Patterns agents use Matrix Client-Server API for, with concrete tasks.
★ Self-Hosted Team Chat Client
Companies running a Matrix homeserver (such as Synapse) need a custom client embedded into their internal tools. The Client-Server API covers the core operations: create rooms, invite teammates, sync events, and manage filters. A typical embedded client uses long-poll sync against a homeserver and the room endpoints to drive the UI.
Call `POST /createRoom` with `{name: 'engineering', visibility: 'private'}` then `POST /rooms/{roomId}/invite` for each teammate's MXID.
Bridge and Notification Bots
Bridge bots replicate messages between Matrix and other systems (GitHub, Jira, Slack). The bot authenticates as a Matrix user, joins relevant rooms, and posts events whenever the upstream system fires. The Client-Server API provides everything the bot needs: join rooms, send messages, manage filters to skip noise.
Call `POST /join/{roomIdOrAlias}` to join the alerts room, then post incidents as message events whenever the upstream webhook fires.
Room Moderation Tooling
Community moderators need bulk tools to enforce conduct: kicking spammers, banning repeat offenders, and tightening join rules. The Matrix API exposes per-room kick, ban, and aliasing endpoints that a moderation dashboard can wire into rule-based actions or human review queues.
Call `POST /rooms/{roomId}/ban` with the MXID and a reason to ban a confirmed-spammer account from a moderated room.
AI Agent in Matrix Rooms
An AI agent participating in a Matrix room (answering questions, summarising threads) can use Jentic to call Matrix Client-Server operations on demand. Jentic stores the access token in the vault and exposes operations like 'join a room' or 'send a message' via intent search, so the agent does not have to hand-roll Matrix authentication.
Search Jentic for 'create a matrix room', load the `/createRoom` schema, and execute it with the agent's access token to bootstrap a project room.
Key Endpoints
32 endpoints — jentic publishes the only available openapi specification for matrix client-server api, keeping it validated and agent-ready.
METHOD
PATH
DESCRIPTION
POST
/createRoom
Create a new Matrix room
POST
/rooms/{roomId}/join
Join a room by ID
POST
/join/{roomIdOrAlias}
Join a room by ID or alias
POST
/rooms/{roomId}/leave
Leave a room
POST
/rooms/{roomId}/invite
Invite a user to a room
POST
/rooms/{roomId}/kick
Kick a user from a room
POST
/rooms/{roomId}/ban
Ban a user from a room
POST
/user/{userId}/filter
Create a user sync filter
POST
/createRoom
Create a new Matrix room
POST
/rooms/{roomId}/join
Join a room by ID
POST
/join/{roomIdOrAlias}
Join a room by ID or alias
POST
/rooms/{roomId}/leave
Leave a room
POST
/rooms/{roomId}/invite
Invite a user to a room
POST
/rooms/{roomId}/kick
Kick a user from a room
POST
/rooms/{roomId}/ban
Ban a user from a room
POST
/user/{userId}/filter
Create a user sync filter
Jentic AI Readiness Score
This API is usable in Jentic One now. Its AI-readiness score against Jentic's framework shows where it stands today and where improvements would make it even easier for agents to use.
M
Matrix Client-Server API
- Non-Ready (D+)48/100
26
Foundational Compliance69
Developer Experience & Jentic Compatibility45
AI-Readiness & Agent Experience94
Agent Usability38
Security80
AI DiscoverabilityPowered by JenticScoring Framework 1.0.0 | Scoring Engine 0.4.0
Show dimension breakdown
26
Foundational Compliance
Base layer of spec validity and structural soundness.
Grade: FSignals: 4
58%
Lint Results
Aggregated quality score from linter diagnostics, weighted by severity.
47%
Resolution Completeness
Percentage of `$ref` references that resolve successfully.
0%
Specification Validity
Checks whether the API description parses successfully and conforms to its declared specification (e.g., OpenAPI).
0%
Structural Integrity
Structural correctness score based on schema issues using logarithmic dampening.
69
Developer Experience & Jentic Compatibility
Clarity, completeness, and ingestion readiness for developers and tooling.
Grade: B+Signals: 4
27%
Example Density
How richly the API is illustrated with examples.
100%
Example Validity
Percentage of examples that conform to their schemas.
50%
Response Coverage
Percentage of operations with complete response definitions (success, client error, server error).
100%
Tooling Readiness
Health of API ingestion, bundling, and resolution within Jentic pipelines.
45
AI-Readiness & Agent Experience
Semantic breadth, depth, and agent comprehension for AI systems.
Grade: DSignals: 4
53%
Description Coverage
Coverage of descriptions across API elements.
0%
Error Standardization
Coverage of RFC 9457 Problem Details for error responses.
100%
OperationId Quality
Coverage, uniqueness, and casing consistency of operationIds for AI inference.
27%
Summary Coverage
Coverage of summaries across operations/tags/info.
94
Agent Usability
Functional utility, complexity comfort, and AI orchestration readiness.
Grade: A+Signals: 1
94%
Complexity Comfort
Agent comfort level based on API operational and structural complexity.
38
Security
Trust, risk posture, and security compliance.
Grade: FSignals: 1
38%
Authentication Strength
Average quality of security schemes based on authentication method strength (weakest link for OAuth2).
80
AI Discoverability
Findability, semantic richness, and reasoning readiness.
Grade: ASignals: 1
80%
Descriptive Richness
Clarity and depth of descriptions across API elements.
Score it yourself
Every API in the directory is allowlisted, so you can re-score it with no key required.
npx @jentic/api-scorecard-cli score <openapi-url>Why Jentic?
What agents get from Jentic-routed access to this vendor.
Setup
Wiring the Matrix Client-Server API by hand means handling bearer access-token auth, resolving the {homeserver} host for your deployment, and mapping room and user operations yourself. Through Jentic you install once, import the Matrix Client-Server API from the API Directory, store the access token once, and your agent calls it.
Permission scoping
Matrix puts the room id in the URL path (/rooms/{roomId}/...), so a rule can pin your agent to one room: it can invite and join for that room and nothing else. You choose the operations it may call, so destructive ones like kick or ban are not included unless you add them.
Credential isolation
Your Matrix access token is stored once, encrypted, by your own Jentic One instance and applied at execution time. It never enters the agent's prompt, logs, or context.
Intent-based discovery
Agents search Jentic by intent such as 'create a Matrix room' or 'invite a user to a room', and Jentic returns the matching Matrix Client-Server operation with its input schema so the agent calls the right endpoint without browsing the reference docs.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using Matrix Client-Server API through Jentic.
Why is there no official OpenAPI spec for Matrix Client-Server API?
The Matrix.org Foundation publishes the Client-Server specification as Markdown plus Swagger fragments rather than a single distributable OpenAPI document. Jentic generates and maintains a unified OpenAPI specification so AI agents and developers can call the Matrix Client-Server API via structured tooling. It is validated against the live API and kept up to date. Get started with Jentic One, the self-hosted execution layer.
What authentication does the Matrix Client-Server API use?
The API supports two authentication schemes: an HTTP bearer token in the `Authorization` header (preferred) and an `access_token` query parameter. Through Jentic, the access token is stored encrypted in your Jentic One instance and applied to each request automatically.
Can I create a new room with the Matrix Client-Server API?
Yes. `POST /createRoom` creates a new room and returns the `room_id` and any aliases. The request body lets you set name, topic, visibility (`public`/`private`), and an initial set of invitees.
What are the rate limits for the Matrix Client-Server API?
Matrix rate limits are enforced per homeserver rather than globally. Synapse, the reference homeserver, applies per-IP and per-user limits configured by the homeserver admin (default ~ 0.1 events per second with bursts up to 10). Inspect the `Retry-After` header on `429` responses and back off accordingly.
How do I join a Matrix room through Jentic?
Run `pip install jentic`, then use Jentic's search with the query 'join a matrix room'. Jentic loads the `/join/{roomIdOrAlias}` operation schema and your agent executes it with the room alias - Jentic injects the access token automatically.
Does the API work against any Matrix homeserver?
Yes. The base URL is parameterised as `https://{homeserver}/_matrix/client/v3`, so the same operations work against matrix.org, a self-hosted Synapse instance, Conduit, Dendrite, or any other compliant homeserver.
Can I limit what my agent is allowed to do with the Matrix Client-Server API?
Yes. Because Jentic One is self-hosted, you write the rules that decide which Matrix operations and which access token your agent may use. Matrix carries the room id in the URL path (/rooms/{roomId}/...), so a rule can pin the agent to a single room and let it only invite and join there. You choose the operation set, so destructive calls like /rooms/{roomId}/kick or /rooms/{roomId}/ban stay out unless you explicitly grant them.
GET STARTED