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

The description states 'Read-only, no side effects,' which aligns with the annotation readOnlyHint=true. It also explains the output format: 'Returns JSON with reflowed text by default; use --raw for plain output.' This adds context beyond the annotation, though the annotation already covers the read-only aspect.

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 three sentences with front-loaded main action, safety, output format, and usage guidance. Every sentence adds value; no wasted words.

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 8 parameters and no output schema, the description explains the output format and basic usage. It does not detail all parameters, but the schema itself is fully documented. The description provides sufficient context for an agent to understand the tool's purpose and behavior.

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?

The input schema has 100% description coverage for all 8 parameters, so the description does not need to re-iterate parameter details. The description mentions the --raw flag and default output, but does not add significant meaning beyond the schema. 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?

The description clearly states the tool's function: 'Reflow paragraphs to a target character width, preserving paragraph boundaries.' It distinguishes from the sibling tool 'fold' by noting that this tool is for reformatting prose without breaking paragraph structure, while 'fold' does hard line wrapping.

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 explicitly says when to use the tool ('Use to reformat prose without breaking paragraph structure') and when not ('Not for hard line wrapping — use 'fold'...'). It also references the sibling tool 'fold' as an alternative, providing clear guidance.

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