Manage PDF form fields

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

The description honestly discloses limitations: 'fill' creates a new overlay rather than mapping onto original AcroForm widgets, 'read' returns text runs not declared AcroForm field objects, and 'validate' only enforces non-empty rule. Annotations already indicate destructiveHint=true, but the description adds valuable context beyond annotations.

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 well-structured with a clear overview, return types listed by operation, behavioral details, limitations, and sibling references. Every sentence is informative and earns its place. It is concise yet complete.

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 the tool's complexity (4 operations, 5 parameters, output schema, annotations), the description covers all essential aspects: return values per operation, side effects (overwriting), limitations, and usage context. No gaps remain for an AI agent to misuse the 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 100%, so baseline is 3. However, the description adds meaningful context: it explains which parameters are required per operation and provides detailed format for 'fields' (e.g., {name, type:'text', x, y, width, height, default_value?}). This goes beyond the schema's minimal descriptions.

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 explicitly states 'Create, fill, read or validate PDF form fields,' clearly identifying the verb (multiple operations) and resource (PDF form fields). It distinguishes from sibling tools like manipulate_pdf and extract_text in the last sentence.

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 provides explicit guidance on when to use which operation (e.g., 'For page-structure edits use manipulate_pdf; to read prose use extract_text') and notes that 'create'/'fill' write and 'read'/'validate' are read-only. It also explains required parameters for each operation.

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