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

Annotations already declare readOnly/idempotent/openWorld, so the description doesn't need to re-state safety. It adds genuinely new behavioral context: the shape of each result (plain-word finding, peptide, evidence class, source passages) and the obligation to display the PepBank credit line. Pagination behavior beyond the schema's cursor note is not addressed.

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?

Four short sentences, front-loaded with purpose, then result shape, then attribution, then usage and the alternative. Nothing is redundant with the schema or annotations.

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, covering result fields and the attribution requirement. Minor gaps remain on result volume and how pagination is meant to be traversed in practice.

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%, so baseline is 3. The description adds meaning beyond the schema by saying the query spans topics, outcomes, or questions (not just keyword matching on peptide names), which shapes how the agent should phrase input.

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 verb and resource ('Search PepBank study findings across all peptides') plus the searchable dimensions (topic, outcome, question). It explicitly contrasts with the sibling peptide_research, so an agent can pick between them without opening a schema.

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?

Gives a concrete trigger example ('which peptides were studied for tendon healing') and names the alternative plus the condition that selects it ('use peptide_research when the user names one peptide'). Both the when and the when-not are present.

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