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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false. The description adds genuinely useful context beyond that: a 2-credit cost and the fact that free-tier behavior only confirms valid lemmas while paid plans return full mappings. However, this distinction is vague about what an agent on the current plan actually receives, and it is partly redundant with the existing output schema.

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?

Three compact sentences with the core transformation front-loaded. The repeated title prefix 'Text Lemmatizer: Text Lemmatizer' is wasted duplication, but the rest is efficient and the cost note is properly parenthetical.

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 one-parameter, read-only transformation tool with an output schema and full annotation coverage, the definition supplies everything needed to call it. The only ambiguity is what the free-tier 'confirms when valid lemmas exist' response actually contains, which the output schema presumably resolves.

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?

There is a single required parameter with 100% schema description coverage ('The text to lemmatize'), so the schema fully carries parameter meaning. The description adds nothing about input format, length limits, or language assumptions, so baseline 3 is appropriate.

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 transformation: reduces inflected words to dictionary base forms. This clearly distinguishes it from more general siblings like Dictionary or PartsOfSpeech, though it never names an alternative explicitly.

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?

Usage is implied by the phrase 'submitted text,' but there is no explicit when-to-use guidance and no mention of when to prefer TenseConverter, PartsOfSpeech, or Dictionary instead. The note about confirmed lemmas vs full mappings hints at conditions but is framed as a plan limitation, not usage guidance.

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