nexus_update_user_donation_preferences

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

Annotations already mark the operation as non-read-only, idempotent, and non-destructive. The description adds valuable behavior: partial-update semantics ('only provided fields are changed; omitted fields stay as-is') and the exact success/error return shape, which is not in the 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 tight sentences lead with the action, state the critical partial-update rule, and give the return contract. No filler; each sentence adds information.

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 7-parameter all-optional update with a full schema, the description is complete: it identifies the affected resource, explains how parameters behave when omitted, and specifies the response shape. Annotations cover idempotency and destructiveness, so no essential calling context 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 100% and every parameter has a description, so the baseline is 3. The description earns an extra point by clarifying that absent parameters are ignored rather than reset to null despite the schema's default: null, which prevents a likely misinterpretation of the partial-update behavior.

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 states a specific verb ('Update') and a precise resource ('the current user's Donation Points preferences') and notes the GraphQL v2 interface. This clearly sets it apart from the sibling getter nexus_get_user_donation_preferences and from generic nexus_update_preferences.

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?

No guidance is given about when to choose this tool instead of sibling update/preference tools. It doesn't mention that reading preferences should use nexus_get_user_donation_preferences or that generic settings belong to nexus_update_preferences; the only cue is the tool name.

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