Character method

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

readOnlyHint=true already tells the agent this is a safe read, and the description adds real value on top with the "call once" idempotency cue and a concrete inventory of what the payload contains. It does not say how the content is formatted or how large the response is, which would matter for a reference dump with no output schema.

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 payload inventory followed by the usage instruction. The long parenthetical list is dense but each item is informative; the only cost is mild run-on density rather than wasted wording.

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?

With no parameters, no output schema, and readOnly already annotated, the description covers what the tool returns and when to call it, which is enough to invoke correctly. The remaining gap is response shape and volume, relevant because a full method plus reference lists is likely a large payload.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate and the baseline is 4. Nothing in the description conflicts with or misrepresents the empty schema.

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?

Uses a specific verb ("Returns") and enumerates exactly what resource is returned: the method core plus 9 sections, card format, variant-tournament protocol, and named reference lists. The enumeration makes it unmistakably distinct from siblings like character_check or character_concept without needing to name them.

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?

"Call once before writing a character" gives clear sequencing and frequency guidance, which is the key usage constraint for a reference-dump tool. It stops short of naming alternatives or stating when-not to use it, so it does not reach the top band.

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