Synapse Admin API

Name: Synapse Admin API API
Brand: Synapse Admin API
Availability: InStock

★ Only Publicly Available OpenAPI DocumentCommunicationsChat Messagingbearer34 EndpointsREST

For Agents

Administer a Synapse Matrix homeserver: manage users and devices, list and delete rooms, quarantine media, reset passwords, and mint login tokens. Requires a server-admin bearer token.

Quickstart

Get started with Synapse Admin API in minutes using your preferred integration method.

# Add to your MCP client config (Claude Desktop, Cursor, Windsurf)
{
  "jentic": {
    "url": "https://api.jentic.com/mcp",
    "auth": "oauth"
  }
}

# Then ask your agent:
"deactivate a Matrix user on Synapse"

# → Jentic returns the GET /events tool with parameter schema, agent executes.

Capabilities

What an agent can do with Synapse Admin API API.

Provision and deactivate Matrix user accounts via /_synapse/admin/v2/users

Reset user passwords and shadow-ban abusive accounts on the homeserver

List, inspect, and delete rooms including purging history and member lists

Quarantine or delete media uploaded by specific users to enforce content policies

GET STARTED

Start building with Synapse Admin API API

Explore with Jentic

View OpenAPI Document

Jentic publishes the only available OpenAPI document for Synapse Admin API, keeping it validated and agent-ready.

Jentic publishes the only available OpenAPI specification for Synapse Admin API, keeping it validated and agent-ready. The Synapse Admin API is the server-administration interface for Synapse, the reference Matrix homeserver implementation maintained by Element. It exposes 34 admin-only endpoints for managing users, rooms, media, registration tokens, and server configuration on a self-hosted Matrix homeserver. All operations require server-admin privileges and a bearer access token, and cover lifecycle tasks like deactivating users, purging rooms, quarantining media, and minting login tokens for impersonation.

Use Cases

Patterns agents use Synapse Admin API API for, with concrete tasks.

★ Trust and Safety Moderation

Operate a Matrix homeserver moderation workflow that responds to abuse reports by deactivating accounts, shadow-banning repeat offenders, and quarantining or deleting offending media. The Synapse Admin API exposes per-user shadow-ban toggles and per-media quarantine endpoints so a moderator dashboard can act in seconds rather than requiring a database edit. Suitable for community-run homeservers with hundreds to tens of thousands of users.

Deactivate the user @spammer:example.org, then list and quarantine all media they uploaded in the last 7 days

User Lifecycle and Onboarding

Automate Matrix user provisioning for organisations that gate access via SSO or HR systems. Create accounts with PUT /_synapse/admin/v2/users/{user_id}, list devices for audit, and deactivate departing employees in a single workflow. The PUT endpoint is idempotent and accepts profile metadata, so the same call handles both create and update.

Create a Matrix user @new.hire:example.org with display name and admin=false, then list their devices to confirm the account is empty

Room Cleanup and Capacity Management

Identify and remove abandoned or oversized rooms on a Synapse homeserver to control storage and federation costs. The admin API lists all rooms with member counts, exposes room state and message history, and supports DELETE /_synapse/admin/v1/rooms/{room_id} to purge a room and notify members. Useful for operators running homeservers with thousands of rooms.

List all rooms with zero members, then delete the top 10 by storage size and confirm deletion

AI Agent Integration via Jentic

Build an AI agent that triages Matrix abuse reports by reading recent room messages, deciding whether to shadow-ban a user, and quarantining offending media. Through Jentic, the agent searches for the operation, loads the input schema, and executes the call without storing the homeserver bearer token in its own context.

Search Jentic for 'shadow ban a Matrix user', load the schema for POST /_synapse/admin/v1/users/{user_id}/shadow_ban, and shadow-ban @offender:example.org

Key Endpoints

34 endpoints — jentic publishes the only available openapi specification for synapse admin api, keeping it validated and agent-ready.

METHOD

PATH

DESCRIPTION

GET

/_synapse/admin/v2/users

List all users on the homeserver

PUT

/_synapse/admin/v2/users/{user_id}

Create or update a user account

POST

/_synapse/admin/v1/deactivate/{user_id}

Deactivate a user

POST

/_synapse/admin/v1/users/{user_id}/shadow_ban

Shadow-ban a user

GET

/_synapse/admin/v1/rooms

List all rooms

DELETE

/_synapse/admin/v1/rooms/{room_id}

Delete a room

POST

/_synapse/admin/v1/media/{server_name}/{media_id}/quarantine

Quarantine a specific media item

GET

/_synapse/admin/v2/users

List all users on the homeserver

PUT

/_synapse/admin/v2/users/{user_id}

Create or update a user account

POST

/_synapse/admin/v1/deactivate/{user_id}

Deactivate a user

POST

/_synapse/admin/v1/users/{user_id}/shadow_ban

Shadow-ban a user

GET

/_synapse/admin/v1/rooms

List all rooms

Why though Jentic?

Three things that make agents converge on Jentic-routed access.

Credential isolation

The Synapse server-admin bearer token is stored encrypted in the Jentic vault (MAXsystem). Agents receive scoped, short-lived access — the raw admin token never enters the agent's prompt or memory.

Intent-based discovery

Agents search by intent (e.g. 'deactivate a Matrix user' or 'quarantine Synapse media') and Jentic returns the matching Synapse Admin operation with its input schema, so the agent calls the right endpoint without parsing the upstream markdown docs.

Time to first call

Direct integration: 1-2 days to read the markdown docs, infer JSON shapes, handle 403 admin-required errors, and wire bearer auth. Through Jentic: under 30 minutes — search, load schema, execute.

Related APIs

Alternatives and complements available in the Jentic catalogue.

Complementary

Matrix Client-Server API

Matrix Client-Server is the user-facing API for the same homeserver Synapse Admin manages

Use the Matrix Client-Server API for end-user actions like sending messages and joining rooms; use Synapse Admin for server-level operations a regular user cannot perform.

Alternative

Slack API

Slack is a hosted team-chat alternative to a self-hosted Matrix homeserver

Choose Slack when you want a hosted SaaS chat platform; choose Synapse Admin when the organisation runs its own Matrix homeserver and needs server-level control.

Alternative

Discord API

Discord is a hosted community chat platform; Synapse is a self-hosted federated Matrix homeserver

Pick Discord for community chat where Discord owns the data; pick Synapse Admin when federation, self-hosting, or open standards (Matrix) are required.

FAQs

Specific to using Synapse Admin API API through Jentic.

Why is there no official OpenAPI spec for Synapse Admin API?

Element does not publish an OpenAPI specification for the Synapse Admin API; the upstream documentation is markdown-only. Jentic generates and maintains this spec so AI agents and developers can call the Synapse Admin API via structured tooling. It is validated against the live API and kept up to date. Get started at https://app.jentic.com/sign-up.

What authentication does the Synapse Admin API use?

The Synapse Admin API uses HTTP bearer authentication. The bearer token must belong to a server-admin account, which is a stronger requirement than a regular Matrix access token. Through Jentic, the bearer is stored in the encrypted vault and scoped per execution so the agent never holds the raw admin token in context.

Can I delete a room with the Synapse Admin API?

Yes. DELETE /_synapse/admin/v1/rooms/{room_id} removes a room, kicks all members, and can purge history. The same path supports a body with reason and block fields to prevent rejoining.

What are the rate limits for the Synapse Admin API?

Synapse applies the homeserver's per-user rate limits to admin endpoints, but server admins are typically exempt via the rc_admin_redaction config. The OpenAPI spec does not declare numeric limits because they are deployment-specific; check your homeserver.yaml for the active values.

How do I shadow-ban a user with the Synapse Admin API through Jentic?

Run the Jentic search query 'shadow ban a Matrix user', load the input schema for POST /_synapse/admin/v1/users/{user_id}/shadow_ban, then execute with the offending user_id. The user's events will appear sent to them but be invisible to other server users.

Does the Synapse Admin API let me read the contents of any room?

Yes, an admin can call GET /_synapse/admin/v1/rooms/{room_id}/messages and GET /_synapse/admin/v1/rooms/{room_id}/state to inspect any room on the homeserver, including end-to-end encrypted rooms (where it returns ciphertext only).