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

Annotations already cover read-only, idempotent, non-destructive, so the description correctly spends its words elsewhere: it discloses that the call is free, that output is portable JSON, and critically that date-learned data is excluded — a scope limitation an agent could otherwise get wrong. No info on size or rate limits, but the exclusion note is the valuable part.

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 sentences, front-loaded with the key qualifier ('Free.') and then the payload contents and the exclusion. Every clause carries information an agent needs; nothing is padded.

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?

No output schema exists, yet the description enumerates the returned fields and explicitly names what is missing, so an agent knows the shape and limits of the result. For a two-parameter read-only export, nothing material is left out.

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 50%: agent_id is documented as optional within a session, character_id is undocumented. The description only indirectly explains agent_id by mentioning 'rebuild if you lose your agent_id', and adds nothing about character_id constraints. Adequate but it does not compensate for the coverage gap.

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 (export the character) and defines the artifact precisely: a create_character-ready JSON containing sheet, voice, extras, soul and partner_style. That round-trip framing separates it well from get_character or update_character, though those siblings are never named explicitly.

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 three concrete use cases — keep, version, or rebuild after losing agent_id — which tells the agent when this call is warranted. It stops short of stating when not to use it (e.g. vs get_character for a quick read), so no explicit exclusions.

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