Sinch Conversation API
✓ Official Vendor SpecCommunicationsSms Messagingbasic, oauth222 EndpointsREST
For Agents
Programmatically send a message, get a message. Covers 22 operations with basic, oauth2 authentication.
Use for: I need to send a message, I want to a message, Search for message metadata, Find all a message
Not supported: Does not handle payments, crm, or developer tools - use for communications only.
The Sinch Conversation API enables sending and receiving messages globally across SMS, RCS, WhatsApp, Viber Business, Facebook Messenger, and other channels through a unified interface. The API exposes 22 endpoints secured with basic, oauth2 authentication.
Install Jentic One Beta
Connect the Sinch Conversation API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Sinch Conversation 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%2Fsinch.com%2Fsinch" | 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%2Fsinch.com%2Fsinch" | 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 Sinch Conversation API.
Send a message
Get a message
Update message metadata
Delete a message
List messages
Fetch last message
Create an app
Use Cases
Patterns agents use Sinch Conversation API for, with concrete tasks.
★ Communications Operations
Use the Sinch Conversation API to perform communications operations programmatically. The API provides 22 endpoints covering core functionality including send a message, get a message, update message metadata.
Call POST /v1/projects/{project_id}/messages:send to send a message
Automated Apps Management
Automate apps operations by combining multiple Sinch Conversation API endpoints. Agents can get a message and then update message metadata in a single workflow.
Call GET /v1/projects/{project_id}/messages/{message_id} to get a message, then verify the result
AI Agent Integration via Jentic
AI agents discover and call Sinch Conversation API endpoints through Jentic without managing credentials directly. An agent searches for the required operation by intent, receives the matching endpoint schema, and executes the call with Jentic-managed authentication. This eliminates the need to read API documentation or handle basic, oauth2 tokens manually.
Search Jentic for 'send a message', load the operation schema, and execute with Jentic-managed credentials
Key Endpoints
22 endpoints — the sinch conversation api enables sending and receiving messages globally across sms, rcs, whatsapp, viber business, facebook messenger, and other channels through a unified interface.
METHOD
PATH
DESCRIPTION
POST
/v1/projects/{project_id}/messages:send
Send a message
GET
/v1/projects/{project_id}/messages/{message_id}
Get a message
PATCH
/v1/projects/{project_id}/messages/{message_id}
Update message metadata
DELETE
/v1/projects/{project_id}/messages/{message_id}
Delete a message
GET
/v1/projects/{project_id}/messages
List messages
POST
/v1/projects/{project_id}/messages:fetch-last-message
Fetch last message
POST
/v1/projects/{project_id}/apps
Create an app
GET
/v1/projects/{project_id}/apps
List apps
POST
/v1/projects/{project_id}/messages:send
Send a message
GET
/v1/projects/{project_id}/messages/{message_id}
Get a message
PATCH
/v1/projects/{project_id}/messages/{message_id}
Update message metadata
DELETE
/v1/projects/{project_id}/messages/{message_id}
Delete a message
GET
/v1/projects/{project_id}/messages
List messages
POST
/v1/projects/{project_id}/messages:fetch-last-message
Fetch last message
POST
/v1/projects/{project_id}/apps
Create an app
GET
/v1/projects/{project_id}/apps
List apps
Why Jentic?
What agents get from Jentic-routed access to this vendor.
Setup
Wiring the Sinch Conversation API by hand means handling its OAuth2 or basic auth, choosing the right US, EU, or BR region host, and carrying tokens across every message call yourself. Through Jentic you install once, import Sinch from the API Directory, store the credentials once, and your agent calls it.
Permission scoping
Sinch puts the project id and message id in the URL path (/v1/projects/{project_id}/messages/{message_id}), so a rule can pin your agent to one project: it can send and read messages there and nothing else. You choose the operations it may call, so destructive ones like deleting a message or creating apps are not included unless you add them.
Credential isolation
Your Sinch credentials are stored once, encrypted, by your own Jentic One instance and injected at execution time. They never enter the agent's prompt, logs, or context.
Intent-based discovery
Agents search Jentic by intent such as 'send a message' or 'fetch the last message in a conversation', and Jentic returns the matching Sinch 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 Sinch Conversation API through Jentic.
What authentication does the Sinch Conversation API use?
The Sinch Conversation API uses basic, oauth2 authentication. Through Jentic, these credentials are stored encrypted in your Jentic One instance and injected at execution time, so raw secrets never enter the agent context.
Can I send a message with the Sinch Conversation API?
Yes. Use the POST /v1/projects/{project_id}/messages:send endpoint. The API returns structured JSON responses that agents can parse and act on directly.
What are the rate limits for the Sinch Conversation API?
Rate limits are not specified in the OpenAPI spec. Check the vendor documentation for current limits. Through Jentic, rate limiting is handled automatically with retry logic built into the execution layer.
How do I send a message through Jentic?
Install the Jentic SDK with pip install jentic, authenticate through Jentic One, the self-hosted execution layer, then search for 'send a message'. Jentic returns the matching Sinch Conversation API operation with its input schema. Load the schema and execute the call - credentials are injected automatically.
How many endpoints does the Sinch Conversation API have?
The Sinch Conversation API exposes 22 endpoints covering apps, capability, contacts operations.
Can I limit what my agent is allowed to do with the Sinch Conversation API?
Yes. Because you run Jentic One yourself, your own rules decide which Sinch operations and credentials your agent may use. Since Sinch puts the project id and message id in the URL path, a rule can pin the agent to a single project so it only sends and reads messages there. You choose the operations it may call, so destructive ones like deleting a message or creating apps stay off limits unless you explicitly add them.
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