Save a fitting in-game

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

Annotations supply only openWorldHint, so the description carries the disclosure burden and does it well. It reveals the required auth scope, a genuine data-loss behavior ('ESI cannot store charges per slot, so loaded charges are dropped (with a warning) unless they are also in the cargo section'), and the return value ('Returns the new fitting_id').

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?

Five short sentences, front-loaded with the action and scope, then the data-loss caveat, then the return value, then the confirmation prompt. No sentence is padding; each carries a distinct fact the agent needs before calling.

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 output schema and only a sparse annotation set, the description covers auth, mutation effect, a silent-data-loss edge case, the returned fitting_id, and a user-confirmation requirement. Nothing essential to calling this four-parameter write tool 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 coverage is 75%, so most parameters are already documented. The description still adds semantic value the schema does not: that names inside the EFT text are 'resolved from static data' and that charge handling inside the `eft` blob has a caveat. It adds meaning rather than repeating the 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?

The description opens with a specific verb and resource: 'Saves an EFT fit to the character's in-game saved fittings.' It distinguishes itself from read-side siblings like fitting_get, fitting_list, and ship_fitting by being explicitly a persistence operation, and even names the exact ESI scope it maps to.

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 states a clear prerequisite and behavioral gate: 'requires esi-fittings.write_fittings.v1' and 'Confirm with the user before saving.' It doesn't explicitly contrast itself with fitting_delete or say when not to use it, but the write intent and the confirmation requirement give an agent enough to route correctly.

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