compare_species

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses that the tool throws an error if a species doesn't exist, that it never compares against invented species, and that it never compares topology. It also explains the underlying data limitation (only human has structural connectivity). This is strong behavioral transparency, though it could have mentioned the exact error type or return format.

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, dense paragraph that front-loads the core purpose and then adds critical constraints. It is somewhat long but every sentence adds value: the combined output, the counting logic, the topology exclusion, and the error behavior. The structure could be improved with bullet points or clearer separation, but it is not bloated.

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?

Given the tool's complexity (comparison logic, data limitations, error handling) and the absence of annotations, the description covers the essential behavioral context. It explains what the tool does, what it doesn't do, and when it errors. The output schema exists, so return values are presumably documented elsewhere. The only minor gap is not specifying the exact format of the species IDs or the structure of the homology list, but the description is largely complete for an agent to select and invoke the tool correctly.

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%, so the description must compensate. The description explains that the two parameters are species IDs and that they must refer to real species, but it doesn't add detail about the format or expected values of the IDs. The description's mention of 'species_a_id' and 'species_b_id' is implicit, not explicit. Baseline 3 is appropriate because the description adds some semantic context (real species, error on non-existent) but doesn't fully elaborate on parameter specifics.

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: comparing two real species by combining a quantitative summary and the complete list of shared homologies. It explicitly names the resource (species) and the specific action (compare), and it distinguishes itself from siblings like compare_species_images and find_homologues by specifying the combined output format.

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 explicit guidance on when to use this tool: it compares real species, never invented ones, and it explicitly states that it does not compare topology between species because only human has real structural connectivity loaded. This directly informs the agent when this tool is appropriate versus when it might need a different tool (e.g., for connectivity comparisons).

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