# Cosmic (slim)

> Cosmic is a hosted headless CMS with a REST API, a TypeScript SDK, a CLI and a hosted MCP server. Agents read and write objects, media and object types, generate media, and can create a project by agent signup.

- Full: https://www.anchorterminal.com/tools/cosmic.md (~6,700 tokens) · this version ~1,530 tokens · JSON https://www.anchorterminal.com/tools/cosmic.json · canonical https://www.anchorterminal.com/tools/cosmic
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-11-07 · pricing https://www.anchorterminal.com/tools/cosmic#pricing · reviews https://www.anchorterminal.com/tools/cosmic#reviews
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)

**BB · 72.5/100 · rank #123 of 1486 · #3 in CMS & website publishing · agent-ready · confidence medium**


Assessment: Cosmic gives agents 24 annotated MCP tools with when-to-use descriptions, a read-only mode by key, documented limits and an agent signup API that returns working keys before a human claims the project. It holds no SOC 2 or ISO certification by its own statement, and read keys can travel in the URL.

## Facts

- Kind: HTTP API · vendor: Cosmic Inc. · category: CMS & website publishing · legal entity: Cosmic Inc. · provenance 73/100
- Endpoint: `https://mcp.cosmicjs.com/v1/buckets/{bucket_slug}` (HTTP, Streamable HTTP, stdio)
- Auth: API key · pricing: Freemium · x402: no · licence: unknown
- Benchmark probes: not run yet, so Performance is pending
- Live, from our pollers (not part of the score): up at 2026-11-07 17:49 UTC · uptime 30 days 100.0% (195 probes) · p50 451 ms · p95 541 ms over 24 hours
- Vendor status page: not read, no machine-readable status found (2026-11-07 04:47 UTC)
- Surface listed: The hosted MCP server at mcp.cosmicjs.com, the bucket REST API at api.cosmicjs.com/v3 and the agent signup API at dapi.cosmicjs.com, read from www.cosmicjs.com (llms.txt, Markdown docs, openapi.json, pricing.md, security, terms, privacy, changelog), the cosmicjs/mcp repository, the MCP registry and the status page on 6 November 2026. No account was made and no tool was called
- MCP tools: Objects (list, get, create, update, delete), media, object types and AI generation of text, images, video and audio into the media library, plus cosmic_agent_signup and two related tools on the agent scope
- Drafts and revisions: Objects have draft and published status; revisions are kept for 30 to 365 days by plan, and reading or restoring them needs the Revision History add-on
- Limits: 100 non-cached requests a second, burst 200, 30-second timeout, 6 MB request and response size, 900 MB uploads; monthly request quotas by plan
- Data location: Content in a replicated MongoDB Atlas cluster, per the security FAQ
- Legal entity: Cosmic Inc., per the MCP server's MIT licence; the terms and privacy policy say Cosmic JS, Plano, Texas
- Prices: Builder plan $99 per month (plan); Team plan $299 per month (plan); Business plan $499 per month (plan)

- Scores: Reliability 90, Performance pending, Schema & documentation 88, Agent ergonomics 82, Security & auth 47, Payments & pricing 45, Task success pending, Maintenance & community 86, Transparency & trust 63 · total over the 7 assessed categories
- Why: Reliability, Graded on the hosted service with the hosted lines. · Schema & documentation, openapi.json at www.cosmicjs.com covers 21 operations on 12 paths, each with a summary, a description and documented 401, 402, 404, 429 and… · Agent ergonomics, 24 tools, in the 11 to 30 band (15), plus 5 because omitting the write key gives a read-only subset (20 of 25). · Security & auth, Separate read and write keys per bucket, rotatable independently (25), less 10 because the docs give `read_key` as a query parameter on GET… · Payments & pricing, No x402, MPP or L402 (0). · Maintenance & community, MCP server v1.7.1 was tagged on 2 November 2026 (30). · Transparency & trust, A closed service; the MCP server is MIT (18 of 30).
- Sources: 14, open questions: 5, both in the full twin
- Capabilities: cms.content, cms.assets, cms.schema, cms.publish, cms.localisation
- JSON: https://www.anchorterminal.com/api/v1/tools/cosmic.json
- Verify (for the vendor): the badge `https://www.anchorterminal.com/badges/cosmic.svg` or a link to https://www.anchorterminal.com/tools/cosmic from a page on cosmicjs.com or one of its subdomains, or the README at the root of github.com/cosmicjs/mcp, then `POST https://www.anchorterminal.com/api/v1/verify` `{"slug", "url"}` or `verify_listing` at /mcp; re-checked weekly, no effect on the grade. Snippets in the full twin.
- Support: Discord https://discord.gg/MSCwQ7D6Mg; support@cosmicjs.com; https://www.cosmicjs.com/docs; https://cosmicstatus.com; more in the full twin

## Before you call it

1. Send only the read key in the Bearer token unless the task needs writes
2. Use cosmic_agent_signup when the user has no Cosmic account, and hand the human the claim URL within 14 days
3. Fix and don't retry on 400; wait and retry on 429
4. Use props, depth=0 and cursor pagination with `after` to stay under the 6 MB response limit
5. Confirm with the user before cosmic_objects_delete, which deletes permanently

## Connect

```bash
npx @cosmicjs/mcp
```

```bash
curl -X POST https://dapi.cosmicjs.com/v3/agents/sign-up -H "Content-Type: application/json" -d '{"human_email":"you@example.com","project_name":"Recipe Blog","agent_id":"my-agent"}'
```
Full config and headless snippets are in the full page. Through letme (picks today, calling later): https://letme.dev/cosmic

## Similar tools

| Tool | Grade | Score | Shared capabilities | Slim |
| --- | --- | --- | --- | --- |
| DatoCMS | BB | 74.4 | cms.content, cms.publish, cms.assets, cms.localisation, cms.schema | https://www.anchorterminal.com/tools/datocms.min.md |
| Sanity | BB | 72.7 | cms.content, cms.publish, cms.assets, cms.schema, cms.localisation | https://www.anchorterminal.com/tools/sanity.min.md |
| Kontent.ai | BB | 70.6 | cms.content, cms.publish, cms.assets, cms.localisation, cms.schema | https://www.anchorterminal.com/tools/kontent-ai.min.md |
| Webflow | BB | 70.4 | cms.content, cms.publish, cms.assets, cms.schema, cms.localisation | https://www.anchorterminal.com/tools/webflow.min.md |
| Strapi | B | 67.7 | cms.content, cms.publish, cms.localisation, cms.assets, cms.schema | https://www.anchorterminal.com/tools/strapi.min.md |


## Panel reviews (0, desk reviews from public material, no calls made)