---
title: "Data and sync"
description: "Declared entities and their limitations."
group: "Product"
order: 5
---

## Deployment addresses

- Documentation: https://ctx4.me/docs.md
- Agent index: https://ctx4.me/docs/agent-index.json
- Console and connections: https://console.ctx4.me/integrations
- MCP: https://ctx4.me/mcp
- HTTP API: https://ctx4.me/v1
- Composio base URL: https://ctx4.me/compat/context4/v1
- OpenAPI: https://ctx4.me/docs/openapi.json
- HTTP/MCP inventory: https://ctx4.me/docs/api-index.json
- Composio routes: https://ctx4.me/docs/compat-routes.json
- Connectors: https://ctx4.me/docs/connectors.json


[Open this deployment's console and connections](https://console.ctx4.me/integrations).

## Choose a data type

Available types are listed on the connector page. If a type is not declared, do not assume it is supported.

## Configure sync

Use an available mode and schedule in the console. The presence of a data type does not imply identical latency or completeness across services.

## Check the state

Before using data, check the sync state and freshness. A source error must not be interpreted as an absence of records.

## What to check before creation

Retrieve the connector's available syncable entities and delivery capabilities. The entity schema, historical reading support, mode and schedule depend on the source. API source provider schema discovery preserves the metadata revision; it does not infer a schema from arbitrary records. Database schema discovery returns declared tables and fields; an empty database can have a valid empty schema.

## Sources and history

Context4 distinguishes object syncs from events without object storage. Provider-event subscriptions can exist without a Sync; an event does not imply that historical reading is available for that service. A historical export is a separate resource with its own state and cancellation. Its availability and boundaries depend on the source.

Schema discovery, database polling and CDC currently support PostgreSQL and SQL Server. MySQL and MongoDB variants remain in the public schemas but are deferred: discovery returns `400 validation_failed`, and creating a sync on such a source is refused as not found.

For database polling, use read-only credentials and a supported mode; the reading mode determines whether deletions are visible. Broker delivery, snapshot and replay do not imply the same guarantee for every provider. Check the actual run status and source limitations.

Exact settings, states, schema hash and fields: [syncs](https://ctx4.me/docs/api-syncs.md), [sources](https://ctx4.me/docs/api-sources.md), [events](https://ctx4.me/docs/api-events.md).