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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint=false, covering the safety profile. The description adds behavioral context by specifying the response includes up to 25 ranked suggestions with specific fields (usage ID, matched name, rank, status, group, higher-taxon context) and that it works against the working draft. This goes beyond the annotations by describing output details and ranking behavior.

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 three sentences, each earning its place. It front-loads the core purpose, then describes the response fields and use cases, and finally the optional rank restriction. No filler or repetition; it is appropriately concise for the information conveyed.

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 3-parameter tool with an output schema, the description is complete. It covers what the tool does, the response structure, use cases, and the optional rank parameter. The limit parameter is adequately described in the schema, and the output schema handles return-value details. Nothing essential for correct invocation is missing.

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 parameters are well-documented. The description adds semantic value by explaining the query is a 'partial or full name prefix', showing an example of rank restriction ('GENUS'), and clarifying that the usage ID is intended for downstream tools. This enriches the schema definitions without redundancy.

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 autocompletes species/taxon names against the Catalogue of Life working draft, returning ranked suggestions. It explicitly mentions the usage ID can be passed to col.species.detail or col.species.children, distinguishing it from those sibling tools. The verb 'Autocomplete' is specific and the resource (Catalogue of Life) is named.

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 context on when to use the tool: 'Ideal for type-ahead name disambiguation in scientific workflows, species identification pipelines, or biodiversity data cleaning tasks.' It also mentions the optional rank restriction, but does not explicitly contrast with col.species.search or state when not to use it. The mention of passing usage ID to other tools implies a workflow, but there is no explicit 'use this instead of X' guidance.

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