Cosmicjs Cosmic API

Name: Cosmic API
Brand: Cosmic API
Availability: InStock

★ Only Publicly Available OpenAPI DocumentMarketingContent Managementbearer, apiKey16 EndpointsREST

For Agents

Manage headless CMS content in Cosmic — list, create, update, and delete objects and object types, upload media, and track object revisions. Supports a bearer Personal Access Token plus per-bucket read/write keys.

Install Jentic One Beta

Connect the Cosmic API to your agent

Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Cosmic 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.

Step 1: Jentic One Host machine

# On the machine that will host your Jentic One instance:
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh

Step 2: Agent machine

# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL https://raw.githubusercontent.com/jentic/jentic-one/main/tools/install.sh | sh
jentic register       # connects your agent to your Jentic One instance

Jentic 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 Cosmic API.

List, create, fetch, update, and delete content objects inside any bucket to power website and app content surfaces

Track object history by adding revisions through the dedicated revisions endpoint

Manage object types — the schemas that define content models — including creating and deleting type definitions

GET STARTED

Start building with Cosmic API

Explore with Jentic

View OpenAPI Document

Use Cases

Patterns agents use Cosmic API for, with concrete tasks.

★ Headless CMS for a Website

Power a marketing site or app by storing pages, blog posts, and reusable components as Cosmic objects, organised by object type. The build pipeline reads objects through the bucket read key, while the editor's CMS uses a Personal Access Token to publish updates that flow into the next build.

On build, call GET /buckets/{bucketSlug}/objects with the bucket read key to fetch all published posts, render the static pages, and invalidate the CDN.

AI-Generated Content Publishing

An AI workflow drafts product descriptions, blog posts, or release notes and publishes them directly into Cosmic by creating typed objects. Each generation that needs revising is recorded as a revision so editors can roll back without losing prior text.

Call POST /buckets/{bucketSlug}/objects with the generated object payload, then POST /buckets/{bucketSlug}/objects/{objectId}/revisions on every subsequent edit so editors can audit the history.

Bulk Media Migration

When migrating assets from another CMS or DAM, upload images and documents to Cosmic in batches, then attach them to existing objects through metafields. The media endpoints support upload, update, and delete so the migration script can clean up failures without manual portal work.

For each asset call POST /buckets/{bucketSlug}/media to upload, store the returned media ID, and PATCH /buckets/{bucketSlug}/objects/{objectId} on the relevant content object to attach the new media reference.

AI Agent Content Operations via Jentic

An agent assists editors with prompts like 'publish this draft as a blog post on Cosmic' or 'archive every product object older than two years' by mapping the request to the right Cosmic operation through Jentic. The agent reasons over content intent rather than memorising bucket slugs and HTTP methods.

Search Jentic for 'create Cosmic object' or 'delete Cosmic object', load the matching operation, and execute it with the bucket slug and object payload provided by the editor.

Key Endpoints

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

METHOD

PATH

DESCRIPTION

GET

/buckets/{bucketSlug}/objects

List objects in a bucket

POST

/buckets/{bucketSlug}/objects

Create a content object

PATCH

/buckets/{bucketSlug}/objects/{objectId}

Update a content object

DELETE

/buckets/{bucketSlug}/objects/{objectId}

Delete a content object

POST

/buckets/{bucketSlug}/objects/{objectId}/revisions

Add an object revision

GET

/buckets/{bucketSlug}/object-types

List object types

POST

/buckets/{bucketSlug}/media

Upload media to a bucket

GET

/buckets/{bucketSlug}/objects

List objects in a bucket

POST

/buckets/{bucketSlug}/objects

Create a content object

PATCH

/buckets/{bucketSlug}/objects/{objectId}

Update a content object

DELETE

/buckets/{bucketSlug}/objects/{objectId}

Delete a content object

POST

/buckets/{bucketSlug}/objects/{objectId}/revisions

Add an object revision

Why Jentic?

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

Credential isolation

The Cosmic Personal Access Token and per-bucket read/write keys are stored encrypted in the Jentic vault (MAXsystem). Agents receive a scoped execution handle — the right credential is injected per operation (bearer for write, query key for read) and never enters the agent's context.

Intent-based discovery

Agents search by intent (e.g., 'create Cosmic object' or 'upload Cosmic media') and Jentic returns the matching operation with input and response schemas, so the agent picks the right endpoint without browsing Cosmic documentation.

Time to first call

Direct Cosmic integration: half a day for auth selection, bucket setup, and metafield mapping. Through Jentic: under 30 minutes — search, load, execute.

FAQs

Specific to using Cosmic API through Jentic.

Why is there no official OpenAPI spec for Cosmic API?

Cosmic publishes API documentation but not a single OpenAPI specification. Jentic generates and maintains this spec so that AI agents and developers can call Cosmic 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 Cosmic API use?

The API supports three credentials: a Personal Access Token with the cos_ prefix sent as a bearer Authorization header, plus per-bucket read_key and write_key values passed as query parameters. Through Jentic, all three are stored encrypted and the right one is injected per operation so the agent never sees the raw secret.

Can I create new content objects with this API?

Yes. POST /buckets/{bucketSlug}/objects creates a new content object inside the named bucket, accepting the object's type slug, metafields, and slug as inputs. Use the bucket write key or a Personal Access Token for this operation.

How do I track changes to a Cosmic object?

Call POST /buckets/{bucketSlug}/objects/{objectId}/revisions after each meaningful edit. Cosmic stores the revision so editors can audit history or roll back without external version control.

What are the rate limits for the Cosmic API?

The OpenAPI spec does not declare numeric rate limits. Treat HTTP 429 responses as authoritative, back off using the Retry-After header where present, and consult the Cosmic dashboard for plan-specific limits before running heavy migrations.

How do I upload media through Jentic?

Search Jentic for 'upload media to Cosmic', load POST /buckets/{bucketSlug}/media, and execute it with the file payload and bucket slug. Jentic returns the operation schema so the agent does not need to read Cosmic docs for the field names.

Cosmicjs Cosmic API

Connect the Cosmic API to your agent

Capabilities

Start building with Cosmic API

Use Cases

Key Endpoints

Why Jentic?

Related APIs

FAQs