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

Annotations (readOnlyHint, openWorldHint, idempotentHint) plus description details data sources per type: SEC EDGAR/XBRL for companies with correct fiscal year handling, FAERS for drugs. Also mentions sorting by primary metric and return of citation URIs.

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?

A single dense paragraph that front-loads examples and guidelines, then gives details. Every sentence adds value, no redundancy. Ideal length for quick agent scanning.

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 tool with no output schema, the description covers return format ('paired data + pipeworx:// citation URIs'), data sources, sorting behavior, and entity types. It's self-contained and complete for agent decision-making.

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 clear param descriptions. Description adds context like 'type="company" pulls LATEST 10-K...' and 'Results sorted by primary metric', which provides meaning beyond the schema. Still, the schema already defines the enum and array constraints well.

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 it performs side-by-side comparisons of 2-5 companies or drugs, with explicit trigger phrases and a specific verb 'compare'. It distinguishes from siblings like 'entity_profile' which does single-entity lookups.

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?

Provides explicit guidance: 'ALWAYS PREFER over sequential single-pack lookups when comparing entities.' Includes trigger examples ('which is bigger', 'rank these companies') and differentiates from alternatives.

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