Check a held tool call by approval_id to see whether it is pending, executing, done, failed, rejected, or expired, and retrieve the downstream result once complete.
Check a held call by its approval_id. Returns its status (pending, executing, done, failed, rejected, expired) and, once done, the downstream result.
| Name | Required | Description | Default |
|---|---|---|---|
| approval_id | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The readOnlyHint annotation already establishes this is a safe read, and the description goes beyond that by disclosing the state machine (pending, executing, done, failed, rejected, expired) and that the downstream result appears only once done. It does not say whether expired/rejected calls can be retried or how long pending states persist, so it stops short of a 5.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two tight sentences with the identifier-based lookup front-loaded and the return shape second. Nothing is redundant or wasted.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
With no output schema, the description usefully enumerates the return values and the conditional downstream result, which is the main thing an agent needs. It is slightly incomplete on where approval_id is obtained and whether repeated polling is expected for pending states.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0% for the single required parameter, so the description must carry the weight. It ties approval_id to the held call being checked, but adds no format, origin (where the id comes from), or validation detail beyond the parameter name itself.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
Description gives a specific verb and resource: 'Check a held call by its approval_id', and states what is returned (status plus downstream result). This distinguishes it from listing tools like list_pending, though it never names a sibling explicitly, keeping it short of a 5.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Usage is only implied: an agent infers it should call this when it holds an approval_id and wants progress. There is no explicit statement of when to use this versus list_pending, nor any guidance on polling cadence or when the check is unnecessary.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.