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

With no annotations provided, the description carries the full burden. It discloses the return format (dict of field names to values) and cost ($0.001 USDC), but does not mention authentication requirements, error behavior on unfilled forms, or that it only reads the file without modification. The return format and price add some context, but gaps remain.

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?

Two concise sentences cover the action, return format, and pricing. No fluff or repetition; every sentence earns its place.

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 simple read-only extraction tool with an output schema present, the description adequately covers the core behavior and return value. It mentions the pricing and the 'filled PDF' prerequisite. Minor gap: it does not specify what happens with empty or non-form PDFs, but overall it is sufficient for a tool of this complexity.

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% parameter description coverage, so the schema already documents all three parameters. The description adds nothing beyond implying that the PDF must be filled, which does not materially enhance parameter understanding. Baseline score of 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 action ('Extract all form field values') and the target resource ('filled PDF form'), which is specific and distinguishes this tool from siblings like fill_form (writing) and list_form_fields (likely just field names).

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 phrase 'from a filled PDF form' implies the tool is for reading values from completed forms, but there is no explicit comparison with sibling tools or guidance on when to use this over list_form_fields. Usage context is implied, not spelled out.

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