Update Achievement

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

Annotations already declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false, so safety is partly covered. The description adds genuinely non-structured behavior: the required role and the subtle rule that passing an empty description clears the field — a mutation semantic an agent could not infer from annotations.

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 short sentences, zero filler, with the core action and the mutable fields front-loaded before prerequisites and the clearing caveat.

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 four-parameter mutation with no output schema, the description covers the essentials: what changes, who may call it, and the minimum-one-field requirement. It omits return behavior and the credential parameter, but neither is likely to block a correct call.

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% — achievementId and userCredentials are documented in-schema, while name and description are bare. The description partially compensates by naming those two fields and explaining the empty-string-clears behavior for description, but it says nothing about the credential parameter or name constraints.

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 ("Update an achievement") plus the exact mutable fields (name, description), which cleanly separates it from the sibling create_achievement, delete_achievement, award_achievement, and list_achievements. An agent can select this 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?

"Requires group Maintainer/Owner" gives an explicit permission prerequisite, and "Provide at least one changed field" states a precondition for a valid call. It does not point at sibling alternatives (e.g., create vs award vs update), so it stops short of full routing guidance.

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