# Troubleshoot Tools

Start with the Tool definition, then inspect **[Activity](/docs/monitor/transcript-and-activity)** in Conversation detail for the exact `tool_call` status, error, duration, arguments, assigned values, and a bounded result preview. Secret values are deliberately absent.

## Request never reaches the endpoint

Operade rejects non-HTTP URLs and any hostname whose DNS answers include a private, loopback, link-local, or otherwise non-global address. DNS is checked before every call, the public address is pinned for the connection, and redirects are not followed. A private address failure therefore happens before your service sees a request.

Also check for a missing path argument, invalid JSON Schema arguments, a deleted Tool, or a missing Secret. These failures occur before HTTP. A timeout uses the Tool's configured limit and is reported to the model without exposing low-level network details.

## Endpoint responds with an error

HTTP 400 or higher is a failed Tool result. The model receives a bounded error, and response assignments are not extracted. Verify method, URL, query/body routing, authentication mode, and the remote service logs. Operade accepts at most 256 KB of response content; keep responses small and return only fields the agent needs.

A successful response does not need to be JSON unless you configured assignments. Empty success responses become an acceptance message. Non-JSON responses can still inform the model, but cannot produce assigned variables.

## Missing or changed behavior

Deleting a Tool does not check active-resource references. Agent Tool lists skip the missing Tool, so attached Agents continue without that ability. A Procedure or Workflow that still depends on it can fail validation or runtime checks. Detach stale IDs, save the draft, and test again before publishing.

Use the [Tool API reference](/docs/api-reference/tools/get-tool) to compare the stored definition, then revisit [parameters](/docs/tools/parameters) and [authentication](/docs/tools/authentication-and-secrets).