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

Annotations already declare this is a non-read-only, non-destructive, non-idempotent mutation, so the safety profile is covered. The description adds the conditional-currentPassword rule, but says nothing about whether existing sessions/tokens are invalidated, whether the change requires an authenticated session, or what happens on failure.

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?

Two short sentences, zero filler, with the core action front-loaded and the conditional requirement immediately after. Nothing is wasted.

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 two-parameter, fully schema-documented tool with clear annotations and no output schema, this covers what an agent needs to invoke it. Only side effects (session invalidation, auth requirements) are absent, which is a minor gap rather than a blocking one.

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 both parameters are already described in the schema ('At least 8 characters', 'Required if a password is already set'). The description's currentPassword clause essentially restates the schema text, adding no new format or constraint detail, so the baseline 3 applies.

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 ('Set a new password'), which is unambiguous and clearly distinct from the account/profile/API-key siblings. It doesn't need to name an alternative because none of the listed siblings overlap with password setting.

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 second sentence conveys a conditional prerequisite (accounts with an existing password must supply currentPassword), which is useful context. However, there is no guidance on when to use this versus update_profile or delete_account, and no mention of authentication state or what happens to existing sessions.

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