Get Full Persona

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

The annotations already mark the call read-only and idempotent, and the description adds valuable behavior beyond that: it guarantees no protocol error on invalid input, instead returning an error object with a fix hint, and it documents the exact response shape with a typical example. The premium plan signal is also useful context not present in 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 structured with a one-line summary, an illustrative example, explicit scope guidance, an error contract, and a retry safety note. Every sentence conveys useful information; the wording is tight and the most decision-relevant facts are front-loaded.

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 single-parameter read-only tool with an output schema, this description is complete: input source, expected output, error format, usage boundaries, sibling alternative, and premium requirement are all covered. There is no obvious missing context an agent would need to call it correctly.

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%, and the schema already states that slug is 'Product slug exactly as returned by search_catalog.' The description reinforces this with a concrete example, but it does not add meaning beyond what the input schema already provides, so the baseline 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 states a specific verb and resource: 'Load a product's complete persona definition' and clearly differentiates this tool from siblings by saying it returns 'the persona text alone, with no skill bodies.' It also names get_full_product as the alternative that includes skills, so an agent can distinguish them without opening schemas.

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 explicitly says when to use this tool: when the caller needs 'the product's voice and operating rules only' and when not to use it: 'Not when skills are also wanted - get_full_product returns persona and every skill in one call.' It also flags premium plan availability, which helps the agent decide within plan constraints.

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