# One vs StackOne

> StackOne scores 69.1 (B) to One's 66.6 (B) for app automation. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/one-vs-stackone
- Markdown: https://www.anchorterminal.com/compare/one-vs-stackone.md (~2,250 tokens)
- Slim: https://www.anchorterminal.com/compare/one-vs-stackone.min.md (~680 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/one-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

StackOne scores 69.1 (B) on agent readiness against One's 66.6 (B), and leads in 4 of 7 scored categories. Both do app automation.

- One: grade B, 66.6/100, rank #282 of 950. Markdown https://www.anchorterminal.com/tools/one.md · JSON https://www.anchorterminal.com/api/v1/tools/one.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

## Which one, for what

### One (B)

Good for: A person or small team that wants one MCP entry with a small tool footprint across many SaaS accounts, with access set per connection and a free plan.

Also in its favour:
- Runs on your own machine

Watch for: The remote server's tools changed from four to three by 30 September 2026, and the site's changelog, last dated 13 July 2026, has no entry for it

### 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:
- Payments & pricing, 38 against 30
- Transparency & trust, 69 against 63

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

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 | One | StackOne | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 82 | 80 | One +2 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 77 | 78 | StackOne +1 |
| Agent ergonomics | 13% (16.2 this run) | 73 | 75 | StackOne +2 |
| Security & auth | 14% (17.5 this run) | 69 | 69 | even |
| Payments & pricing | 10% (12.5 this run) | 30 | 38 | StackOne +8 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 86 | 84 | One +2 |
| Transparency & trust | 7% (8.8 this run) | 63 | 69 | StackOne +6 |
| Negative events | ≤15 | -3 | -2 | |
| **Total** | | **66.6 · B** | **69.1 · B** | |

## Facts side by side

| Fact | One | StackOne |
| --- | --- | --- |
| Kind | MCP server | MCP server |
| Vendor | One Systems, Inc. | StackOne Technologies Limited |
| Hosted endpoint | `https://mcp.withone.ai/mcp` | `https://mcp.stackone.com/mcp` |
| Transports | Streamable HTTP, stdio | Streamable HTTP, HTTP |
| Auth | OAuth or key | OAuth or key |
| Pricing | Freemium | Freemium |
| x402 | no | no |
| Licence | Proprietary hosted service under One's Terms of Service. The local MCP server package `@withone/mcp` is MIT. The CLI package `@withone/cli` has no licence field or licence file. The knowledge base is under the One Knowledge Commons Licence v1.0, which is not an OSI licence | 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 | 3 | none |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| MCP registry | `ai.withone/mcp` | `com.stackone/mcp` |
| Last release | 2026-10-06 | 2026-09-24 |
| Terms last updated | 2026-03-06 | 2026-03-30 |
| Privacy policy last updated | 2026-07-22 | 2023-12-01 |
| Customer content may train models | not found in the text | not found in the text |
| Terms restrict automated access | not found in the text | not found in the text |
| Terms restrict benchmarking | yes | 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 | 11 stars, 681 npm/wk | 30 stars, 277 npm/wk |

## Verdicts

**One.** One's remote MCP server has three tools, OAuth 2.1 sign-in with PKCE and a consent screen that sets read only, read and write, full or per-action access for each connection. A person must sign in through a browser, the SOC 2 audit is unfinished, and the site's changelog stops at 13 July 2026.

**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

### One

1. Call `list_one_integrations` first and read each connection's `access` field. When the policy is `actions`, run those ids directly without calling `find_one_actions`
2. Send every operation a task needs in one `find_one_actions` call, up to 10 `requests`, each a platform and a short intent with no IDs, names or message text
3. When a document comes back as a digest, call `find_one_actions` again with `load` and a `section` name. Don't guess parameters the digest left out
4. After a timeout on `execute_one_action`, check whether the write took effect before sending it again. No idempotency key is documented
5. A 403 for a call outside the grant won't succeed on retry. Ask the user to widen the grant in the dashboard or reconnect

### 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, One or StackOne?

StackOne scores 69.1 (B) on agent readiness against One's 66.6 (B), and leads in 4 of 7 scored categories.

### Do One and StackOne need an API key?

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

### Can an agent call One and StackOne without installing anything?

Yes. One has a hosted endpoint at https://mcp.withone.ai/mcp and StackOne at https://mcp.stackone.com/mcp.


## For agents

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

## Other comparisons with One or StackOne

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