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

Annotations already declare readOnly/idempotent/openWorld/non-destructive, so safety is covered; the description adds genuinely new behavioral context: dual Markdown + structuredContent output, the {"result": <paradigm>} shape, the need to switch on result.category before reading the body, and source/license attribution. It stops short of noting rate limits or failure modes beyond not_found, but the additions are substantive.

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?

Front-loaded with the action, then the usage constraint, then the return contract and license. Dense but every clause carries information; the parenthetical asides make it slightly harder to scan than a strictly linear sentence would be.

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 two-parameter read tool with full annotation coverage, a complete schema, and a declared output schema, the description supplies the missing link (how to obtain the handle, what the response category means). Nothing essential is absent.

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 the baseline is 3, but the description adds provenance meaning the schema lacks: both parameters come from a search result's 'inflection handle', tying entry_id/word_class to a prior tool call rather than leaving them as bare strings.

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 (fetch) and resource (declension/conjugation tables for a lemma), names the identifying inputs (entry_id + word_class), and covers both nominals and verbs including mediopassive. An agent can distinguish it from norse_search immediately.

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 when-to-use condition: 'Use this only when a search ran without inline forms or left a match un-expanded', plus the exclusion that a default search already returns tables inline. This routes the agent away from redundant calls.

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