isProposalMessage

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

With no annotations, the description carries the full burden. The verb 'checks' implies a read-only boolean return, which is a useful behavioral cue. However, it does not disclose return type, error behavior, or handling of non-proposal inputs. This is sufficient for a simple predicate but lacks depth.

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 a single, concise sentence that front-loads the action ('Checks if...'). It contains no filler or redundancy, earning high marks for conciseness and efficient structure.

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 tool has no output schema, so the description should clarify what the tool returns, but it does not. It also fails to explain what a 'proposal message' is or how the result should be interpreted. Given the low complexity (one parameter) and lack of output schema, the description is incomplete for a fully contextual understanding.

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?

The input schema already provides 100% coverage for the single parameter 'proposal', describing it as 'The ATC exemption proposal.' The tool description only refers to 'a given object,' adding no extra meaning beyond the schema. With full schema coverage, the baseline score of 3 is appropriate.

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: 'Checks if a given object is a proposal message.' The verb 'checks' and the specific resource 'proposal message' provide a clear purpose. It is distinct from siblings like 'atcExemptProposal' or 'atcRequestExemption' because it is a predicate, though it does not explicitly contrast with alternatives.

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 provides no guidance on when to use this tool versus other tools. It does not mention any context, prerequisites, or exclusions. The only hint is the tool's name and the parameter description, but the description itself offers no usage direction.

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