Update a draft agent's config (partial)

Partial update of a DRAFT agent's config. Send one or more of the agent type's own config fields — the same fields as its POST /business/agents/{type} body, without start. Keys are merged over the saved config: omitted fields keep their value, an array replaces the stored array, and unknown keys are dropped. Sending listName renames both the agent and the results list it will create. The merged config is re-validated against the type's schema, so a partial edit can still be rejected (422 VALIDATION_FAILED). Only drafts (status: initializing) are editable — a started, paused, expired or failed agent answers 409 AGENT_NOT_A_DRAFT, so duplicate it and edit the copy. Nothing is billed. The answer is the saved agent, in the same shape as GET /business/agents/{agentId}.

Errors:

• 404 AGENT_NOT_FOUND — No agent with this id belongs to the token owner. A deleted agent and another user's agent answer identically.
• 409 AGENT_NOT_A_DRAFT — The agent is not a draft (status is not initializing): it was already started, or is paused, expired or failed. Only drafts are editable and activatable — duplicate the agent and work on the copy.
• 409 AGENT_CONFIG_MISSING — The draft carries no stored config to work from (a legacy draft saved before configs were persisted). Create the agent again.
• 409 AGENT_TYPE_UNSUPPORTED — The agent is of a legacy kind this API can no longer edit or activate; its type reads as null.
• 422 VALIDATION_FAILED — The update was rejected by validation. Either this endpoint's own request validation (a malformed agentId, an empty body), where param names the offending field; or the merged config failed the agent type's own schema, which the agents service reports without per-field detail, so param is null and message is the generic one. Re-check the fields you sent against that type's create body.
• 429 RATE_LIMITED — The agents bucket is exhausted: 30 requests per minute or 2,000 per day per token owner, shared by every /business/agents operation (a 429 raised by the agents service is relayed with this code too). Retry after the Retry-After header.
• 500 UNEXPECTED_ERROR — The agents service failed (5xx, refused service credential, or a timeout after 60s) or the rate limiter was unavailable. Retry later; quote request_id to support.

Requires one of the following token scopes: agents.