# One vs Unified.to MCP Server

> One scores 66.6 (B) to Unified.to's 61.9 (C) for app automation. Prices, MCP, x402, uptime and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/one-vs-unified-to-mcp
- Markdown: https://www.anchorterminal.com/compare/one-vs-unified-to-mcp.md (~2,300 tokens)
- Slim: https://www.anchorterminal.com/compare/one-vs-unified-to-mcp.min.md (~680 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/one-vs-unified-to-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: 2026-10-09

One scores 66.6 (B) on agent readiness against Unified.to MCP Server's 61.9 (C), 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
- Unified.to MCP Server: grade C, 61.9/100, rank #455 of 950. Markdown https://www.anchorterminal.com/tools/unified-to-mcp.md · JSON https://www.anchorterminal.com/api/v1/tools/unified-to-mcp.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.

Ahead on:
- Reliability, 82 against 73
- Security & auth, 69 against 50

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

### Unified.to MCP Server (C)

Good for: A B2B software team that already uses or plans to use Unified's API and wants the same customer connections exposed to an LLM, with data read live from the source app.

Watch for: The default credential is a workspace API key. The docs say it grants access to all connections and the whole Unified.to account


## Score by category

| Category | Weight | One | Unified.to MCP Server | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 82 | 73 | One +9 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 77 | 81 | Unified.to MCP Server +4 |
| Agent ergonomics | 13% (16.2 this run) | 73 | 71 | One +2 |
| Security & auth | 14% (17.5 this run) | 69 | 50 | One +19 |
| Payments & pricing | 10% (12.5 this run) | 30 | 30 | even |
| 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 | 66 | Unified.to MCP Server +3 |
| Negative events | ≤15 | -3 | -3 | |
| **Total** | | **66.6 · B** | **61.9 · C** | |

## Facts side by side

| Fact | One | Unified.to MCP Server |
| --- | --- | --- |
| Kind | MCP server | MCP server |
| Vendor | One Systems, Inc. | Unified API Inc. |
| Hosted endpoint | `https://mcp.withone.ai/mcp` | `https://mcp-api.unified.to/mcp` |
| Transports | Streamable HTTP, stdio | Streamable HTTP |
| Auth | OAuth or key | OAuth or key |
| Pricing | Freemium | Paid |
| 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 Unified.to's Terms of Service. The linked repository is sample client code |
| Tools exposed | 3 | none |
| Read-only variant documented | no | no |
| llms.txt | yes | yes |
| MCP registry | `ai.withone/mcp` | `to.unified/core` |
| Last release | 2026-10-06 | 2026-10-08 |
| Terms last updated | 2026-03-06 | no date given |
| Privacy policy last updated | 2026-07-22 | 2026-10-02 |
| 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 | yes |
| 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 | 22k 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.

**Unified.to MCP Server.** Every previewed tool carries a typed input schema and read-only, destructive and idempotent annotations, and the list can be narrowed by permission or tool name. The default credential is a workspace API key that reaches every connection, and the SSE transport was removed on 23 September 2026 in the changelog entry that announced it.

## 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

### Unified.to MCP Server

1. Use the host for the workspace's region. US is `mcp-api.unified.to`, EU is `mcp-api-eu.unified.to` and AU is `api-au.unified.to`. A credential on another region's host resolves to not found
2. Send the key as `Authorization: Bearer <key>` and put `connection=<id>` in the URL. Without `connection` the server lists workspace management tools, not the customer's data tools
3. Pass `tools` or `permissions` in the URL before listing. An unfiltered connection can list dozens of tools with large output schemas
4. Expect HTTP 429 on tool calls since 23 September 2026. Unified does not queue or retry, so back off and retry yourself
5. Page with `limit` (100 at most on most endpoints) and `offset`, and stop when a page returns fewer records than `limit`

## Questions

### Which is better for AI agents, One or Unified.to MCP Server?

One scores 66.6 (B) on agent readiness against Unified.to MCP Server's 61.9 (C), and leads in 4 of 7 scored categories.

### Do One and Unified.to MCP Server need an API key?

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

### Can an agent call One and Unified.to MCP Server without installing anything?

Yes. One has a hosted endpoint at https://mcp.withone.ai/mcp and Unified.to MCP Server at https://mcp-api.unified.to/mcp.


## For agents

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

## Other comparisons with One or Unified.to MCP Server

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