Clean hidden Unicode

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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the bar is lower; the description still adds real context: local/no-API-key execution, that the output includes change counts, that matches may be legitimate text, and a warning to review before overwriting. It does not contradict any annotation.

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?

Five short sentences, front-loaded with the action and scope, with no redundancy; the caution and the negative disambiguation each carry distinct information.

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 values need not be explained, and the annotations carry the safety profile; the description supplies the local-execution fact and the review-before-replacing warning. Only marginal gaps remain, such as handling of text that exceeds limits or yields no changes.

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?

With a single parameter at 100% schema coverage, the schema already documents the input and the 20,000 UTF-16 code-unit limit. The description adds no format or content guidance (e.g. what counts as an 'invisible character') beyond the schema, so 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?

The description states a specific verb and resource ('Locally normalize invisible characters, unusual spaces and Latin lookalikes from Cyrillic/Greek') and explicitly rules out a neighboring concern ('This is not authorship detection'), which separates it from neuroslop_check. An agent can distinguish it from its siblings without opening the 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?

The description implies usage through a caution ('review changes before replacing the original') but never states when to pick this over neuroslop_check or neuroslop_humanize, nor any prerequisites beyond 'no network or API key'. The routing decision is left to inference.

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