zen_form_fill

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

Describes matching order (CSS selector → name → label → placeholder) and value setters (.value, .checked, value for selects). Discloses return format (per-key results). With no annotations, this provides solid behavioral insight, though side effects or error handling are not mentioned.

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 succinct sentences plus an example; no unnecessary words. Front-loaded with the main purpose.

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?

Covers essential behavior (matching, setting, return) despite no output schema. Missing explanation of `tab_id` parameter, but overall adequate for a form fill tool.

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 0%, but description explains the `fields` parameter in detail with matching strategy and example. The `tab_id` parameter is not described, but it's optional with a default, so the main parameter is well covered.

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?

Description clearly states 'Fill many fields at once via fuzzy matching', distinguishing it from sibling like zen_fill (likely single field) and zen_forms. Uses specific verb 'fill' and resource 'fields'.

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?

Implicitly conveys when to use (batch filling with fuzzy matching), but does not explicitly contrast with alternatives or provide when-not-to-use conditions.

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