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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered by structured data. Beyond that the description's main behavioral contribution is the return payload — what fields come back, including photo credit and pending iNaturalist observations — but it says nothing about invalid-key behavior, caching, or result size for a record this broad.

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?

It is a single long comma-separated run-on list of a dozen-plus fields with no grouping or punctuation hierarchy, which makes it harder to scan than it needs to be. It is front-loaded correctly with the key/scope, and no clause is truly wasted, but the structure could be tightened.

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 carries the return-value burden and does so thoroughly by enumerating the record's contents. Combined with 100% schema coverage on the one required parameter and annotations covering the safety profile, the definition is nearly complete; only error/failure behavior is absent.

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% with a single 'key' parameter, so the baseline is 3; the description earns additional credit by telling the agent where a valid key comes from (find_species or list_species), which the schema does not state.

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 states a specific resource and scope — one species of India, keyed by a species key — and enumerates the detail payload (sources, records, IUCN status, taxonomy, evidence, vernacular names, photo, iNaturalist observations), which unambiguously identifies it as the single-record detail lookup. Sibling differentiation is implied by the parenthetical 'from find_species or list_species', though the verb itself is left implicit in the noun-phrase opener.

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 parenthetical '(from find_species or list_species)' gives explicit routing context: obtain a key from a finder or lister first, then call this. That is clear prerequisite/chain guidance, but there is no statement of when not to use it or how it compares to count_species/new_species.

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