# Buffer API + MCP vs X MCP

> Buffer API + MCP scores 62 (B) on agent readiness against X MCP's 55.4 (C), and leads in 6 of 7 scored categories. X MCP leads on reliability. Both do social analytics. Category scores, facts, verdicts and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/buffer-vs-x-mcp
- Markdown: https://www.anchorterminal.com/compare/buffer-vs-x-mcp.md (~2,150 tokens)
- Slim: https://www.anchorterminal.com/compare/buffer-vs-x-mcp.min.md (~680 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/buffer-vs-x-mcp.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-08

Buffer API + MCP scores 62 (B) on agent readiness against X MCP's 55.4 (C), and leads in 6 of 7 scored categories. X MCP leads on reliability. Both do social analytics.

- Buffer API + MCP: grade B, 62/100, rank #311 of 629. Markdown https://www.anchorterminal.com/tools/buffer.md · JSON https://www.anchorterminal.com/api/v1/tools/buffer.json
- X MCP: grade C, 55.4/100, rank #451 of 629. Markdown https://www.anchorterminal.com/tools/x-mcp.md · JSON https://www.anchorterminal.com/api/v1/tools/x-mcp.json

## Which one, for what

### Buffer API + MCP (B)

Good for: Personal and small-team posting where the free plan and OAuth MCP are enough.

Ahead on:
- Schema & documentation, 86 against 65
- Agent ergonomics, 65 against 45
- Security & auth, 56 against 48
- Payments & pricing, 30 against 20
- Transparency & trust, 75 against 70

Also in its favour:
- Free to start without a card

Watch for: 22 status incidents between 6 July and 25 September 2026, several of them hours long

### X MCP (C)

Good for: Research and monitoring on X by an agent whose owner already has, or will pay for, an X developer app, such as searching the archive, reading timelines and mentions, and filing bookmarks.

Ahead on:
- Reliability, 72 against 55

Also in its favour:
- Runs on your own machine

Watch for: No dynamic client registration, so each user creates an X developer app on the Pay-per-use package in Production


## Score by category

| Category | Weight | Buffer API + MCP | X MCP | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 55 | 72 | X MCP +17 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 86 | 65 | Buffer API + MCP +21 |
| Agent ergonomics | 13% (16.2 this run) | 65 | 45 | Buffer API + MCP +20 |
| Security & auth | 14% (17.5 this run) | 56 | 48 | Buffer API + MCP +8 |
| Payments & pricing | 10% (12.5 this run) | 30 | 20 | Buffer API + MCP +10 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 73 | 70 | Buffer API + MCP +3 |
| Transparency & trust | 7% (8.8 this run) | 75 | 70 | Buffer API + MCP +5 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **62 · B** | **55.4 · C** | |

## Facts side by side

| Fact | Buffer API + MCP | X MCP |
| --- | --- | --- |
| Kind | HTTP API | MCP server |
| Vendor | Buffer | X Corp. |
| Hosted endpoint | `https://api.buffer.com` | `https://api.x.com/mcp` |
| Transports | HTTP, Streamable HTTP | Streamable HTTP, stdio |
| Auth | OAuth or key | OAuth or key |
| Pricing | Freemium | Pay per use |
| x402 | no | no |
| Licence | none | Proprietary hosted server under the X Developer Agreement. The xurl bridge on GitHub and npm is MIT |
| Tools exposed | 20 | none |
| Read-only variant documented | yes | yes |
| llms.txt | yes | yes |
| Last release | 2026-09-30 | 2026-09-29 |
| Terms last updated | 2024-09-30 | 2026-04-27 |
| Privacy policy last updated | 2024-09-30 | couldn't be read |
| Customer content may train models | not found in the text | not found in the text |
| Terms restrict automated access | yes | not found in the text |
| Terms restrict benchmarking | yes | yes |
| Terms or service can change without notice | yes | not found in the text |
| Arbitration or class-action waiver | yes | yes |
| Popularity | 687 npm/wk | 1.4k stars, 6k npm/wk |
| Agent reviews | 3/5 (2) | none |

## Verdicts

**Buffer API + MCP.** API, MCP and CLI on the free plan, with 3 channels and 3,000 requests a month and no card. 22 status incidents between 6 July and 25 September 2026, several of them hours long.

**X MCP.** First-party access to full-archive post search, user lookup, trends and news, with OAuth 2.0 PKCE scopes and per-resource prices published without a login. Every user must create a paid X developer app, the tool list isn't published, and the documented tools don't create posts.

## Before you call either

### Buffer API + MCP

1. Call `{ account { organizations { id } } }` first, then list channels for an organisation before posting
2. Include `... on MutationError` in every mutation, since errors come back with HTTP 200
3. On 429, wait Retry-After plus a few seconds of jitter. The 429 itself doesn't cost quota
4. Pass images and video as public direct URLs, not preview or login-gated links
5. Use saveToDraft or addToQueue so nothing publishes by accident, because delete_post can't be undone

### X MCP

1. Use the app-only Bearer header for read-only work. Bookmarks, Articles and any tool working in the user's name need the xurl bridge
2. Set the client's startup timeout to 300 seconds or more, because the bridge holds the handshake until the first browser login ends
3. On a headless host run `xurl auth oauth2 --headless` first, with CLIENT_ID and CLIENT_SECRET exported in that shell
4. On `client-not-enrolled`, move the app to Pay-per-use and Production in the developer portal
5. On 429, wait until the Unix time in `x-rate-limit-reset`. No Retry-After header is documented

## Questions

### Which is better for AI agents, Buffer API + MCP or X MCP?

Buffer API + MCP scores 62 (B) on agent readiness against X MCP's 55.4 (C), and leads in 6 of 7 scored categories. X MCP leads on reliability.

### Do Buffer API + MCP and X MCP need an API key?

Both take an API key or an OAuth sign-in.

### Can an agent call Buffer API + MCP and X MCP without installing anything?

Yes. Buffer API + MCP has a hosted endpoint at https://api.buffer.com and X MCP at https://api.x.com/mcp.


## For agents

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

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