# Cosmic vs Payload

> Cosmic scores 72.5 (BB) to Payload's 50.1 (D) for content management. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/cosmic-vs-payload
- Markdown: https://www.anchorterminal.com/compare/cosmic-vs-payload.md (~4,500 tokens)
- Site index for agents: https://www.anchorterminal.com/llms.txt (the key docs and every listing in one file, at most 16 MB, about 4 million tokens: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- MCP: https://www.anchorterminal.com/mcp (the whole catalogue as tools, no key)
- DNS: dig +short TXT <slug>.grade.anchorterminal.com (the grade as a DNS TXT record, for a sandbox with no HTTP where names still resolve; also top., best.<category>. and <a>.vs.<b>. under the zone, and the same under grade.letme.dev)
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)
- Updated: 2026-11-07

Cosmic scores 72.5 (BB) on agent readiness against Payload's 50.1 (D), and leads in 4 of 7 scored categories. Payload leads on security & auth. Both do content management.

- Cosmic: grade BB, 72.5/100, rank #123 of 1486. Markdown https://www.anchorterminal.com/tools/cosmic.md · JSON https://www.anchorterminal.com/api/v1/tools/cosmic.json
- Payload: grade D, 50.1/100, rank #1068 of 1486. Markdown https://www.anchorterminal.com/tools/payload.md · JSON https://www.anchorterminal.com/api/v1/tools/payload.json
- Best headless CMS and website publishing for AI agents: https://www.anchorterminal.com/best/cms/index.md
- All 136 cms comparisons: https://www.anchorterminal.com/compare/cms/index.md

## Which one, for what

### Cosmic (BB)

Good for: Teams that want an agent to set up and fill a hosted CMS end to end, including signup.

Ahead on:
- Reliability, 90 against 76
- Schema & documentation, 88 against 70
- Agent ergonomics, 82 against 64
- Maintenance & community, 86 against 78

Also in its favour:
- Agent-ready, a grade of BB or better
- A hosted endpoint, with nothing to install
- Runs on your own machine
- Free to start without a card
- No incidents deducted, where Payload loses 15 points for them

Watch for: No SOC 2, ISO 27001 or HIPAA certification, by the security page's own statement

### Payload (D)

Good for: Teams that build on Next.js and want the content model in TypeScript, with drafts, versions and localisation in the free core.

Ahead on:
- Security & auth, 57 against 47

Also in its favour:
- Open source

Watch for: 38 security advisories on OSV in the 12 months to 4 November 2026, 7 critical, 28 published on 6 and 7 October


## Why the edge

### Schema & documentation: Cosmic +18

- Cosmic (88): 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 500 responses, though the docs describe more endpoints than it covers (revisions, AI, search); MCP tools have typed inputs (20 of 25). llms.txt and every docs page as Markdown (10). Tool descriptions say when to use each tool and when not to, such as never calling delete speculatively (18 of 20). 11 enums in the spec, typed metafields and validation messages (11 of 15). Examples on every API page and an error model with a sample (14 of 15). API v3 paths and a dated changelog (15). 20+10+18+11+14+15 = 88.
- Payload (70): No OpenAPI file is published or generated by the core packages, because endpoints depend on each project's config. Every MCP tool carries a typed input schema built from the collection's fields, and the GraphQL schema is generated from the same config (20 of 25). llms.txt per major version, llms-full.txt and a Markdown copy of every docs page (10). Default MCP tool descriptions are one line, such as `Create a document in a collection.`, unless the owner writes one in the plugin config. The docs tell owners to do so (10 of 20). Field inputs are typed with bounds on `limit` and `depth`, but `where` is JSON passed as a string. `select` became an object in the MCP find tools in 3.91.0 (10 of 15). REST operations show a request and a response each. No reference page for error responses or status codes was found (8 of 15). Semver, release notes on GitHub and separate docs per major version. REST paths carry no version (12 of 15).

### Agent ergonomics: Cosmic +18

- Cosmic (82): 24 tools, in the 11 to 30 band (15), plus 5 because omitting the write key gives a read-only subset (20 of 25). limit, props, depth, cursor pagination with `after`, status and locale filters (20). Status codes with specific messages and fix-or-retry guidance per code (17 of 20). readOnlyHint and destructiveHint on the MCP tools; no idempotency keys for writes, though agent signup is idempotent (14 of 20). Few required parameters, a TypeScript SDK and a CLI, no SDK in a second language found (11 of 15). 20+20+17+14+11 = 82.
- Payload (64): Four MCP tools per enabled collection and two per global, so five collections give 20 tools, the 11 to 30 band (15). We added 7 because the owner enables collections and operations one by one, each key narrows the list again, and find tools default to 10 documents at depth 0 with `select` (22 of 25). Page-based pagination with `limit` and `page`, 17 `where` operators, `sort`, `select` and `populate` (20). REST errors come back in an `errors` array and MCP tools return a text line beginning `Error:`. Neither format is documented as a list an agent can match on (10 of 20). No idempotency keys, and no `readOnlyHint` or `destructiveHint` in the plugin source. An update by id is repeatable (4 of 20). Few required parameters and sensible defaults. The one official client, `@payloadcms/sdk` for TypeScript, is labelled beta (8 of 15).

### Reliability: Cosmic +14

- Cosmic (90): Graded on the hosted service with the hosted lines. Statuspage at cosmicstatus.com with API and Web Dashboard components (20). The history page shows no incidents in September, October or November 2026, and the newest incident in the feed is from 26 May 2025. The MCP server isn't a component, so 25 of 30. 100 requests a second with a burst of 200, timeouts and size limits are documented (15). 429 is documented and the error page says which codes to fix and not retry; no Retry-After guidance was found. Agent signup is idempotent (12 of 15). The security page says Enterprise has an SLA from 99.95 per cent uptime; the SLA page itself wasn't read (8 of 10). Hosted MCP is announced as available now, with no beta label (10). 20+25+15+12+8+10 = 90.
- Payload (76): Read with the local-software lines, since the graded surface is software its owner hosts. Official npm packages, with Node.js `^22.23.4 || >=24.22.1` in `engines` and in the installation docs since 3.92.0 (20). A public `ci` workflow runs unit, type, integration and end-to-end tests on every push to 3.x. GitHub's pages and API couldn't be read on 4 November, so the result is unread (15 of 25). 499 issues were open on 8 October, 140 of them awaiting triage, with 225 opened and 116 closed since 10 July 2026, not re-read (12 of 25). A written semver policy marks breaking commits with `!` and lists them in release notes, but lets security fixes and experimental APIs change in minor releases (14 of 15). 3.x is the stable line, with 4.0 in beta (15).

### Security & auth: Payload +10

- Cosmic (47): Separate read and write keys per bucket, rotatable independently (25), less 10 because the docs give `read_key` as a query parameter on GET (15 of 30). Read-only MCP access by leaving out the write key, four user roles on every plan, and a delete tool told not to run speculatively; no approval step (14 of 20). Objects hold text written by people and AI generation writes into the bucket; no prompt-injection guidance was found (3 of 15). An append-only audit log of security-relevant actions on Workspace or Pro plans (10 of 15). No SOC 2, ISO 27001 or HIPAA by the security page's own statement, no security.txt, reports to support email (5 of 20). 15+14+3+10+5 = 47.
- Payload (57): REST keys are per user, revocable and regenerable, shown once, and limited by that user's access control down to field level. MCP keys carry per-collection, per-operation switches. Both travel only in the Authorization header. Neither expires, and there is no OAuth (24 of 30). A find-only MCP key is a config switch away and the collection's access control still runs under it. Nothing asks a person to approve a delete or a publish in the free edition (14 of 20). Documents hold text written by other people, and no prompt-injection guidance was found. `overrideResponse` can strip fields before they reach a model (3 of 15). Versions record each change, and `onEvent` and `verboseLogs` expose MCP calls to the owner's own logging. No built-in audit log (7 of 15). SECURITY.md gives a reporting address and, since 16 October 2026, says Payload pays no monetary rewards and runs no bug bounty. Advisories are published on GitHub with affected versions, patches and workarounds. No security.txt or SOC 2 statement was found (9 of 20).

### Maintenance & community: Cosmic +8

- Cosmic (86): MCP server v1.7.1 was tagged on 2 November 2026 (30). v1.7.0 on 9 September and v1.7.1, plus changelog entries on 14 and 31 August, 1, 8, 10, 22 and 23 September and 5 and 9 October 2026 (20). A dated changelog, a Discord server and support email; GitHub issue activity wasn't read because the GitHub API refused us for its rate limit (12 of 25). com.cosmicjs/mcp in the official MCP registry under a domain namespace, though the registry has 1.6.0 while the repository is at 1.7.1 (15). CI, deploy and publish workflows in the MCP repository (9 of 10). 30+20+12+15+9 = 86.
- Payload (78): 3.92.1 is tagged on 27 October 2026, 8 days before this check (30). Nine stable releases from 3.87.1 on 6 August to 3.92.1 on 27 October 2026, with 4.0.0 betas alongside, which don't count (20). 225 issues opened against 116 closed since 10 July, 140 open issues awaiting triage and 763 open pull requests, per the 8 October check (12 of 25). `@payloadcms/sdk` ships with each release but is beta and TypeScript only, and the official MCP registry has no Payload entry, which fits a plugin that runs inside each install (8 of 15). CI runs on every push. The latest 3.x run had failed on 8 October 2026, and runs couldn't be read on 4 November (8 of 10).

## Score by category

| Category | Weight | Cosmic | Payload | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 90 | 76 | Cosmic +14 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 88 | 70 | Cosmic +18 |
| Agent ergonomics | 13% (16.2 this run) | 82 | 64 | Cosmic +18 |
| Security & auth | 14% (17.5 this run) | 47 | 57 | Payload +10 |
| Payments & pricing | 10% (12.5 this run) | 45 | 45 | even |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 86 | 78 | Cosmic +8 |
| Transparency & trust | 7% (8.8 this run) | 63 | 65 | Payload +2 |
| Negative events | ≤15 | 0 | -15 | |
| **Total** | | **72.5 · BB** | **50.1 · D** | |

## Facts side by side

| Fact | Cosmic | Payload |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | Cosmic Inc. | Payload CMS, Inc. (Figma) |
| Hosted endpoint | `https://mcp.cosmicjs.com/v1/buckets/{bucket_slug}` | no (local only) |
| Transports | HTTP, Streamable HTTP, stdio | HTTP, Streamable HTTP |
| Auth | API key | API key |
| Pricing | Freemium | Free |
| x402 | no | no |
| Licence | none | MIT for the core and the official packages. Enterprise add-ons are sold separately through sales |
| Tools exposed | 24 | none |
| Read-only variant documented | yes | no |
| llms.txt | yes | yes |
| MCP registry | `com.cosmicjs/mcp` | not listed |
| Last release | 2026-11-02 | 2026-10-27 |
| Terms last updated | no date given | no document linked |
| Privacy policy last updated | no date given | 2024-03-28 |
| Customer content may train models | not found in the text | not read yet |
| Terms restrict automated access | yes | not read yet |
| Terms restrict benchmarking | not found in the text | not read yet |
| Terms or service can change without notice | not found in the text | not read yet |
| Arbitration or class-action waiver | yes | not read yet |
| Popularity | 295 npm/wk | 45k stars, 1.1M npm/wk |

## How the scores have moved

### Cosmic

No score change since it was listed.

### Payload

- -5.4 on 4 November 2026 (C to D): new evidence, correction
- +0.3 on 27 October 2026: checklist

## Verdicts

**Cosmic.** 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.

**Payload.** Payload generates REST, GraphQL and MCP interfaces from one typed config, with drafts, restorable versions and per-key MCP permissions in the free MIT core. The security record is the limit. 38 advisories were published in the 12 months to November 2026, most on 6 and 7 October, so an install older than 3.90.0 is exposed. No OpenAPI file is published.

## Before you call either

### Cosmic

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

### Payload

1. Check the installed version first. Anything below 3.90.0 carries published critical advisories, and 3.92.0 and later need Node.js 22.23.4 or 24.22.1, so ask the owner to upgrade before writing
2. Send REST keys as `Authorization: {collection-slug} API-Key {key}` and MCP keys as `Authorization: Bearer {key}`. The two key kinds are separate
3. To publish, set `_status: 'published'` in the data. The `draft` parameter only relaxes validation and chooses where an update is written
4. Upload files with multipart POST to the upload collection, with other fields as JSON in `_payload`. No MCP upload tool is documented
5. Roll back with `POST /api/{collection-slug}/versions/:id` after listing versions. Versions exist only where the collection config enables them

## Questions

### Which is better for AI agents, Cosmic or Payload?

Cosmic scores 72.5 (BB) on agent readiness against Payload's 50.1 (D), and leads in 4 of 7 scored categories. Payload leads on security & auth.

### Do Cosmic and Payload need an API key?

Both need an API key.

### Can an agent call Cosmic and Payload without installing anything?

Cosmic has a hosted endpoint at https://mcp.cosmicjs.com/v1/buckets/{bucket_slug}. No hosted endpoint is listed for Payload.

### Are Cosmic and Payload open source?

No open-source release is listed for Cosmic. Payload is open source (MIT for the core and the official packages. Enterprise add-ons are sold separately through sales).


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/cosmic-vs-payload.json, and with the fewest tokens: https://www.anchorterminal.com/compare/cosmic-vs-payload.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "cosmic", "b": "payload"}`. From a terminal: `anchor compare cosmic payload`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/cosmic.json and https://www.anchorterminal.com/api/v1/tools/payload.json

## Other comparisons with Cosmic or Payload

- [BCMS vs Cosmic](https://www.anchorterminal.com/compare/bcms-vs-cosmic.md)
- [BCMS vs Payload](https://www.anchorterminal.com/compare/bcms-vs-payload.md)
- [ButterCMS vs Cosmic](https://www.anchorterminal.com/compare/buttercms-vs-cosmic.md)
- [ButterCMS vs Payload](https://www.anchorterminal.com/compare/buttercms-vs-payload.md)
- [Contentstack vs Cosmic](https://www.anchorterminal.com/compare/contentstack-vs-cosmic.md)
- [Contentstack vs Payload](https://www.anchorterminal.com/compare/contentstack-vs-payload.md)
- [Cosmic vs DatoCMS](https://www.anchorterminal.com/compare/cosmic-vs-datocms.md)
- [Cosmic vs Directus](https://www.anchorterminal.com/compare/cosmic-vs-directus.md)
- [Cosmic vs dotCMS](https://www.anchorterminal.com/compare/cosmic-vs-dotcms.md)
- [Cosmic vs Ghost](https://www.anchorterminal.com/compare/cosmic-vs-ghost.md)
- [Cosmic vs Hygraph](https://www.anchorterminal.com/compare/cosmic-vs-hygraph.md)
- [Cosmic vs Kontent.ai](https://www.anchorterminal.com/compare/cosmic-vs-kontent-ai.md)
- [Cosmic vs Prismic](https://www.anchorterminal.com/compare/cosmic-vs-prismic.md)
- [Cosmic vs Sanity](https://www.anchorterminal.com/compare/cosmic-vs-sanity.md)
- [Cosmic vs Storyblok](https://www.anchorterminal.com/compare/cosmic-vs-storyblok.md)
- [Cosmic vs Strapi](https://www.anchorterminal.com/compare/cosmic-vs-strapi.md)
- [Cosmic vs Webflow](https://www.anchorterminal.com/compare/cosmic-vs-webflow.md)
- [Cosmic vs WordPress](https://www.anchorterminal.com/compare/cosmic-vs-wordpress.md)
- [DatoCMS vs Payload](https://www.anchorterminal.com/compare/datocms-vs-payload.md)
- [Directus vs Payload](https://www.anchorterminal.com/compare/directus-vs-payload.md)
- [dotCMS vs Payload](https://www.anchorterminal.com/compare/dotcms-vs-payload.md)
- [Ghost vs Payload](https://www.anchorterminal.com/compare/ghost-vs-payload.md)
- [Hygraph vs Payload](https://www.anchorterminal.com/compare/hygraph-vs-payload.md)
- [Kontent.ai vs Payload](https://www.anchorterminal.com/compare/kontent-ai-vs-payload.md)
- [Payload vs Prismic](https://www.anchorterminal.com/compare/payload-vs-prismic.md)
- [Payload vs Sanity](https://www.anchorterminal.com/compare/payload-vs-sanity.md)
- [Payload vs Storyblok](https://www.anchorterminal.com/compare/payload-vs-storyblok.md)
- [Payload vs Strapi](https://www.anchorterminal.com/compare/payload-vs-strapi.md)
- [Payload vs Webflow](https://www.anchorterminal.com/compare/payload-vs-webflow.md)
- [Payload vs WordPress](https://www.anchorterminal.com/compare/payload-vs-wordpress.md)

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Query this catalogue directly over MCP: https://www.anchorterminal.com/mcp (Streamable HTTP, no key). How: https://www.anchorterminal.com/agents/#mcp