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

Annotations already declare readOnlyHint=true, idempotentHint=true, openWorldHint=false and destructiveHint=false, so the safety profile is fully covered by structured data. The description adds the workflow signal that this is a one-time prerequisite read, but discloses nothing about cost, rate limits, or the practical weight of the call beyond what the schema's 'compact/full' level already implies. Adequate but not additive.

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?

Two sentences, zero filler. The purpose and content inventory come first and the sibling routing note is deferred to the end where it belongs.

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?

An output schema exists, so return-value documentation is unnecessary. Combined with complete schema coverage and full annotations, the description supplies everything an agent needs: what it returns, when to call it, and which sibling to use for a narrower question.

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% – both 'lang' (en/fr) and 'level' (compact ~3k tokens vs full every field) are fully documented in the schema with defaults. The description adds no parameter syntax or behavior beyond that, so the baseline 3 applies.

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?

Specific verb+resource ('Return the reference card of the uniwire format for electrical diagrams') followed by an enumeration of the actual contents: document skeleton, node types, fields, enums, links, pitfalls, examples. It explicitly contrasts itself with the sibling type_info, so an agent can route between the two 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?

States both the timing ('Read it once before writing a document') and the alternative with its distinguishing scope ('type_info gives the fields of one type in detail'). When-to-use and when-to-use-something-else are both explicit.

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