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

Annotations already declare readOnlyHint, openWorldHint, idempotentHint, and destructiveHint as false. Description adds value by specifying the nature of returned data (aggregated cross-references) and accepted input varieties, but does not contradict annotations. No annotation contradiction.

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?

Three sentences efficiently cover purpose, inputs, and use case. No unnecessary words; all sentences contribute directly to tool understanding.

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?

Description covers purpose, inputs, and output characteristics (cross-references to specific databases). No output schema exists, but description explains what is returned. Could mention pagination limits, but schema includes size parameter with description.

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 each parameter described. Description adds concrete examples (e.g., 'aspirin', 'chembl.pref_name:aspirin') that enhance understanding beyond the schema definitions, justifying a slightly above-baseline score.

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?

Description clearly states the tool searches MyChem.info for drugs/chemical compounds, specifies accepted input types (plain name, InChIKey, fielded query), and explains the output (aggregated hits with cross-references). It distinguishes from siblings by focusing on chemical entity resolution.

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?

Description includes a use case ('resolve a drug name into structured identifiers') and gives example queries. However, it does not explicitly state when not to use this tool or mention alternatives among siblings, missing an opportunity for clearer guidance.

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