Update an achievement

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

With no meaningful safety annotations, the description carries the behavioral disclosure: omitted fields are preserved, slug is immutable, and changing it would break shipped builds. It also flags name and description as display-only, which helps an agent understand side effects.

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?

Three sentences with the core operation first, then partial-update behavior, then the critical slug restriction. There is no filler and each sentence contains a decision-relevant fact.

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?

The description plus fully documented schema gives identification via game and slug, ownership scope, patch semantics, and restrictions. It doesn't state what the tool returns or confirm the response shape, which would be helpful since no output schema exists.

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?

Because schema coverage is 100%, the baseline is 3, but the description adds global parameter behavior: omissions keep existing values and slug is deliberately not patchable. This is not fully explicit for every optional field in the schema, making it a genuine addition.

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 the precise action — 'Edits one achievement on a game you own' — giving the verb, resource, and ownership scope in one sentence. It also separates this from define/delete/reorder siblings by spelling out patch semantics and the non-patchable slug.

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 partial-update sentence and 'on a game you own' make the intended context explicit: modify an already-existing achievement you own, leaving omitted fields untouched. It doesn't name sibling tools like define_achievement or delete_achievement, but the use case is clear enough that an agent won't need to guess.

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