webmcp_get_invocation

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full burden of behavioral disclosure. It explicitly states side effects are none, that it is read-only state access, and that it returns a JSON structure with a defined set of status values. It also discloses the prerequisite about invocationId coming from webmcp_invoke_tool, which is valuable behavioral context.

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?

The description is efficiently organized: purpose first, then side effects, prerequisites, return format, and usage scenario. Every sentence adds useful information without filler, making it easy for an agent to parse and act on.

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?

The description is complete for a state-polling tool: it covers the expected output shape, possible status values, the read-only side-effect profile, and conditions under which the invocationId is available. No output schema is present, but the description supplies sufficient return structure information.

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 100%, so the baseline is 3. The description adds extra meaning for invocationId by clarifying that it must come from webmcp_invoke_tool and may be found in timeout errors, which goes beyond the schema's simple 'Invocation identifier' description.

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?

The description clearly states the tool's function: returning the current status and result of a WebMCP tool invocation by invocationId. It distinguishes itself from related siblings by explicitly naming webmcp_invoke_tool as the source of the ID and webmcp_list_invocations as the alternative for viewing all invocations.

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?

The description gives explicit guidance on when to use this tool: to poll a long-running invocation, such as one awaiting human approval on a consent dialog. It also names the alternative, webmcp_list_invocations, and clarifies that invoking this tool is non-blocking, making the usage context very clear.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.