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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering safety. The description adds useful context about the output content (both unlocked and locked achievements plus fields), but does not mention pagination, rate limits, or return format. This adds some value but not rich behavioral disclosure.

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?

A single sentence with no filler. The core action and resource are front-loaded, and the qualifier 'unlocked and locked' adds precise scope immediately. Every word earns its place.

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 simple list tool with no parameters and no output schema, the description covers the essential facts an agent needs: it returns all achievements, including both states, with descriptions and unlock dates. It does not specify ordering or pagination, but these are minor for a straightforward read-only list.

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?

There are zero parameters, so the schema is fully covered and no parameter explanation is needed. The description compensates by briefly describing what the returned list will contain, which is helpful given the absence of an output schema. Baseline 4 is appropriate for a no-parameter tool.

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 ('List all achievements') and immediately clarifies scope ('unlocked and locked') with the returned fields ('descriptions and unlock dates'). Among many list_* siblings, the unique resource makes it distinguishable without opening the schema.

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 description implies when to use it: whenever a full list of all achievements is needed. However, there is no explicit when-not-to-use guidance or mention of alternative tools, though no achievement-specific alternatives exist among siblings. The 'all' wording sets a clear context but leaves no exclusions or special cases.

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