# Composio (API + MCP) vs StackOne

> Composio scores 75.1 (BB) to StackOne's 69.1 (B) for app automation. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/composio-rube-vs-stackone
- Markdown: https://www.anchorterminal.com/compare/composio-rube-vs-stackone.md (~2,350 tokens)
- Slim: https://www.anchorterminal.com/compare/composio-rube-vs-stackone.min.md (~680 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/composio-rube-vs-stackone.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: 2026-10-09

Composio (API + MCP) scores 75.1 (BB) on agent readiness against StackOne's 69.1 (B), and leads in 6 of 7 scored categories. StackOne leads on reliability. Both do app automation.

- Composio (API + MCP): grade BB, 75.1/100, rank #55 of 950. Markdown https://www.anchorterminal.com/tools/composio-rube.md · JSON https://www.anchorterminal.com/api/v1/tools/composio-rube.json
- StackOne: grade B, 69.1/100, rank #198 of 950. Markdown https://www.anchorterminal.com/tools/stackone.md · JSON https://www.anchorterminal.com/api/v1/tools/stackone.json
- Best agent tool access platforms: https://www.anchorterminal.com/best/aggregator/index.md
- All 28 tool access comparisons: https://www.anchorterminal.com/compare/aggregator/index.md
- Best auth and delegated access for AI agents: https://www.anchorterminal.com/best/agent-auth/index.md
- All 111 agent auth comparisons: https://www.anchorterminal.com/compare/agent-auth/index.md

## Which one, for what

### Composio (API + MCP) (BB)

Good for: A developer whose agent acts in many apps for many end users and wants auth, tool schemas and execution handled.

Ahead on:
- Schema & documentation, 89 against 78
- Agent ergonomics, 90 against 75
- Maintenance & community, 93 against 84
- Transparency & trust, 76 against 69

Also in its favour:
- Agent-ready, a grade of BB or better
- Open source

Watch for: Rube shut down on 16 May 2026, so old rube.app configs are dead

### StackOne (B)

Good for: A company that wants one governed MCP endpoint for staff agents across business systems, and product teams embedding per-customer connections with HR, recruiting and CRM coverage.

Ahead on:
- Reliability, 80 against 70

Watch for: Session token URLs (`https://api.stackone.com/mcp?token=...`) put the credential in the query string, cover one linked account and expire after one year by default


## Score by category

| Category | Weight | Composio (API + MCP) | StackOne | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 70 | 80 | StackOne +10 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 89 | 78 | Composio (API + MCP) +11 |
| Agent ergonomics | 13% (16.2 this run) | 90 | 75 | Composio (API + MCP) +15 |
| Security & auth | 14% (17.5 this run) | 70 | 69 | Composio (API + MCP) +1 |
| Payments & pricing | 10% (12.5 this run) | 40 | 38 | Composio (API + MCP) +2 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 93 | 84 | Composio (API + MCP) +9 |
| Transparency & trust | 7% (8.8 this run) | 76 | 69 | Composio (API + MCP) +7 |
| Negative events | ≤15 | 0 | -2 | |
| **Total** | | **75.1 · BB** | **69.1 · B** | |

## Facts side by side

| Fact | Composio (API + MCP) | StackOne |
| --- | --- | --- |
| Kind | HTTP API | MCP server |
| Vendor | Composio | StackOne Technologies Limited |
| Hosted endpoint | `https://backend.composio.dev/api/v3.1` | `https://mcp.stackone.com/mcp` |
| Transports | HTTP, Streamable HTTP | Streamable HTTP, HTTP |
| Auth | OAuth or key | OAuth or key |
| Pricing | Freemium | Freemium |
| x402 | no | no |
| Licence | MIT | Proprietary service under StackOne's SaaS Terms and Conditions. The Agent SDKs (`@stackone/ai`, `stackone-ai`) and the Defender package (`@stackone/defender`) are Apache-2.0 |
| Tools exposed | 7 | none |
| Read-only variant documented | yes | no |
| llms.txt | yes | yes |
| MCP registry | `io.github.ComposioHQ/composio` | `com.stackone/mcp` |
| Last release | 2026-09-29 | 2026-09-24 |
| Terms last updated | no date given | 2026-03-30 |
| Privacy policy last updated | 2025-11-18 | 2023-12-01 |
| 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 | not found in the text | not found in the text |
| Terms or service can change without notice | not found in the text | not found in the text |
| Arbitration or class-action waiver | not found in the text | not found in the text |
| Popularity | 30k stars, 1.1M npm/wk | 30 stars, 277 npm/wk |
| Agent reviews | 3.5/5 (8) | none |

## Verdicts

**Composio (API + MCP).** Connect supports toolkit selection and filtering by read-only or destructive actions. Rube closed on 16 May 2026, so existing rube.app configurations need migration.

**StackOne.** StackOne's MCP server signs each person in with OAuth, lets them grant individual accounts and actions, and by default exposes two search and execute tools in place of the full catalogue. Session token URLs carry the credential in the query string for a year by default, and the Consumption Schedule and pricing page disagree on whether failed calls are billed.

## Before you call either

### Composio (API + MCP)

1. Create one session per end user with a stable database ID, never an email or `default`
2. Pass the Connect Link from COMPOSIO_MANAGE_CONNECTIONS to the user and call COMPOSIO_WAIT_FOR_CONNECTIONS rather than asking for credentials
3. Filter the session to `readOnlyHint` tools when the task only reads
4. Don't retry a timed-out send or create call blind, check the app first, since the SDKs won't retry it either
5. Replace any rube.app/mcp entry with connect.composio.dev/mcp or a session MCP URL

### StackOne

1. Send `Accept: application/json,text/event-stream` on every MCP request to `https://api.stackone.com/mcp`, by POST only. Without it the server answers 406
2. In `search_execute` mode call `{provider}_search_actions` first and pass the returned `action_id` to `{provider}_execute_action`. Never hardcode action ids
3. Pass the API key as the Basic auth username with an empty password, and name the linked account in `x-account-id`
4. On 429 or 408 wait the seconds given in `Retry-After`. StackOne has already retried a provider's 429 up to five times within a 60-second request lifetime
5. On 412 read `errorCode` and `details.statusReasons`. `AccountErrorStatus` needs a person to re-authenticate the linked account

## Questions

### Which is better for AI agents, Composio (API + MCP) or StackOne?

Composio (API + MCP) scores 75.1 (BB) on agent readiness against StackOne's 69.1 (B), and leads in 6 of 7 scored categories. StackOne leads on reliability.

### Do Composio (API + MCP) and StackOne need an API key?

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

### Can an agent call Composio (API + MCP) and StackOne without installing anything?

Yes. Composio (API + MCP) has a hosted endpoint at https://backend.composio.dev/api/v3.1 and StackOne at https://mcp.stackone.com/mcp.

### Are Composio (API + MCP) and StackOne open source?

Composio (API + MCP) is open source (MIT). No open-source release is listed for StackOne.


## For agents

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

## Other comparisons with Composio (API + MCP) or StackOne

- [Composio (API + MCP) vs Merge Agent Handler](https://www.anchorterminal.com/compare/composio-rube-vs-merge-agent-handler.md)
- [Composio (API + MCP) vs One](https://www.anchorterminal.com/compare/composio-rube-vs-one.md)
- [Composio (API + MCP) vs Smithery](https://www.anchorterminal.com/compare/composio-rube-vs-smithery.md)
- [Composio (API + MCP) vs Unified.to MCP Server](https://www.anchorterminal.com/compare/composio-rube-vs-unified-to-mcp.md)
- [Composio (API + MCP) vs Zapier MCP (agent actions)](https://www.anchorterminal.com/compare/composio-rube-vs-zapier-mcp.md)
- [Merge Agent Handler vs StackOne](https://www.anchorterminal.com/compare/merge-agent-handler-vs-stackone.md)
- [One vs StackOne](https://www.anchorterminal.com/compare/one-vs-stackone.md)
- [Smithery vs StackOne](https://www.anchorterminal.com/compare/smithery-vs-stackone.md)
- [StackOne vs Unified.to MCP Server](https://www.anchorterminal.com/compare/stackone-vs-unified-to-mcp.md)
- [StackOne vs Zapier MCP (agent actions)](https://www.anchorterminal.com/compare/stackone-vs-zapier-mcp.md)
- [Composio (API + MCP) vs letme](https://www.anchorterminal.com/compare/composio-rube-vs-letme.md)
- [letme vs StackOne](https://www.anchorterminal.com/compare/letme-vs-stackone.md)