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

Annotations provide the safety profile (readOnlyHint: true, destructiveHint: false), confirming it's a read operation. The description adds context about returning 'current plan limits' and 'a complete example payload,' which is useful operational detail beyond the standard JSON shape.

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 extremely efficient, using a single sentence to define the schema, the function of that schema, and the critical operational context (plan limits), achieving maximum information density without unnecessary 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?

Despite having no input parameters, the description is highly complete by detailing the comprehensive nature of the return object, specifically mentioning both the JSON shape and the 'current plan limits.' This is a complete definition for a discovery 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% with 0 parameters, leading to the baseline score of 3. However, the description implies that the returned object will contain structural information and limits, providing high context even without parameter details.

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 defines the tool's role as returning the JSON structure (schema) used by the suite of document creation tools (create_invoice_pdf, etc.). It explicitly distinguishes itself from siblings by mentioning it is the informational prerequisite.

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?

It provides a clear condition for use: 'Call this first if you are unsure how to structure a document,' effectively placing it as the primary discovery tool before creation.

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