fcs_compare

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

With no annotations, the description carries the burden and does add value: it says the tool explains comparability and explicitly treats incomparability as a valid partial-order result rather than a deficiency. It does not disclose return format, error behavior, or side effects, though a compare operation is naturally read-only.

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; the first front-loads the action and expected output, the second preempts a common misconception. No filler.

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?

For a two-parameter tool with no output schema, the description conveys the result's semantic content (ordering or incomparability) and the subtle partial-order interpretation. It stops short of specifying the exact returned shape, but the agent has enough to select and invoke it 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 coverage is 100% and both parameters already have clear descriptions with examples; the description adds only the 'species–function pair' context. That meets the baseline but supplies no parameter-level meaning beyond the schema.

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?

States a specific operation ('Compare') on a specific resource ('two species–function pairs') and the expected output (why they are ordered or incomparable). It doesn't explicitly distinguish itself from fcs_taxonomy or fcs_conformance, but the compare action is clearly unique among siblings.

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 implies the obvious use case—whenever an agent needs the ordering relationship between two species–function pairs—but it provides no explicit when/when-not guidance or alternatives among the many fcs_* siblings. There are no exclusions, but nothing steers an agent away from similar tools.

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