One vs StackOne

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.

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