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

Annotations already declare readOnly, openWorld, idempotent, and non-destructive behavior. The description adds useful context beyond those: 'Verified source: EPO OPS', '24-hour cache', automatic patent number normalization, and the citation direction semantics. No contradiction with annotations.

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 front-loaded with purpose and usage, then parameter details, source/cache info, and a feedback fallback. It is longer than minimal but each section earns its place; minor redundancy exists with annotations ('Read-only. No side effects. Idempotent.').

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?

Given rich annotations, an output schema, and full schema coverage, the description covers all essential aspects: purpose, when to use, parameter formats, normalization behavior, source reliability, cache duration, and a fallback feedback mechanism. Nothing critical 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?

Although schema coverage is 100%, the description substantially enriches parameter understanding: it explains EPODOC format with concrete examples across EP, CN, JP, WO, and US, clarifies that jurisdiction is only an optional hint, and states that normalization makes mismatched jurisdiction valid.

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 opens with a specific verb and resource: 'Fetch forward and backward citation chains for a specific patent.' It clearly differentiates from the sibling legal_search_patents_by_keyword by stating the tool is for citation chains on a known patent, not topic search.

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?

Explicit guidance is provided: 'Use this when building a prior art citation chain for a specific patent you already have. Use legal_search_patents_by_keyword instead when you need to find patents by topic not by citation.' This gives the agent a clear decision rule between alternatives.

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