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

Annotations already declare readOnlyHint=false, destructiveHint=false and openWorldHint=false, so the safety profile is known. The description adds meaningful behavior beyond that: the call returns the created persona with its id, and it has no effect until attached to prompts — useful side-effect disclosure for a write tool.

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?

Front-loaded with the verb and resource, followed by the field explanation and the deferred-effect caveat. The first sentence is long and carries a parenthetical example, but every clause contributes information.

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 5-parameter creation tool with no output schema, the description covers purpose, key fields, return value and effect timing. It omits edge cases like duplicate names or validation failure behavior, but nothing essential to calling it correctly is missing.

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 description coverage is 100%, so the baseline is 3. The description does add flavor to "context" ("the words the buyer would say before asking") with a concrete example, but name, language and location are largely restated from the schema, so it adds only marginal meaning.

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?

States a specific verb and resource ("Create a buyer persona for a site") and the return value ("return it with its id"). The closing clause distinguishes it from prompt-mutating siblings by noting it changes nothing until applied via add_prompts, update_prompt or bulk_update_prompts.

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?

Gives clear context for what a persona is and when it takes effect (only once set on prompts, naming the three tools that do so). It does not state explicit exclusions, such as when to use update_persona instead of creating a new one, so it falls short of a full 5.

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