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

Annotations are minimal (readOnlyHint=false, no value for destructive or idempotent), and the description adds key behavioral constraints: a minimum of 3 reference samples and the fact that it returns a voice profile, reusable prompts, and the rewritten draft. It doesn't explain side effects or permissions, but the operation is a text transformation, so details are sufficient.

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 two sentences with no wandering. It front-loads the core purpose, then quickly lists requirements and output. Every clause adds information; no redundancy or filler.

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 moderately complex tool (two inputs, output schema present), the description covers the goal, the required inputs, the output structure, and the typical use-case. With an output schema provided, the description doesn't need to explain the return values, and it still manages to state what the result includes. Nothing critical is missing.

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%, and the description adds no extra meaning beyond what the schema provides (minItems on reference_samples, descriptions of draft and reference_samples). It touches on the requirement of 'at least 3 reference samples' but that's already encoded. 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 clearly states the tool's function: extract a creator's voice DNA and rewrite a draft in their style. It provides a specific verb+resource and so distinct outcome that it will be useful to an agent. While it doesn't explicitly name alternatives or siblings, its specificity (voice DNA, style matching) distinguishes it from casual rewriting tools.

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 'Use when the user wants to write in another creator's style or match a specific voice' gives clear direction. However, it doesn't mention when not to use it or point to an alternative (e.g., viral_remix or analyze_account), so it offers a clear context but no exclusions.

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