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

Annotations already declare readOnlyHint=false, destructiveHint=true, idempotentHint=true, and openWorldHint=false, so the safety profile is covered. The description adds the auth scope requirement, which is genuinely useful, but it does not explain partial-update semantics or what destructiveness entails for this resource.

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 with zero filler, front-loading the core operation and then the permission requirement. Every sentence 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 an 8-parameter mutation tool with no output schema, the description covers the identifier and write scope but omits important behavioral context such as whether the update is partial or full-replacement and what side effects the destructive hint implies. Annotations and the rich schema compensate partially, leaving this adequate but incomplete.

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 description coverage is 100%, so all 8 parameters (id, name, status, dates, etc.) are already documented in the input schema. The description only restates the required 'by ID' parameter and adds no syntax, format, or update-semantics detail beyond the schema.

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 resource ('project phase') and adds the 'by ID' identifier constraint, which makes the operation concrete. It does not distinguish itself from the many sibling update_* tools (e.g., update_project, update_project_task) beyond naming the resource.

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 only contextual guidance is the required scope ('Requires project_phases:write scope'), which is useful but is a prerequisite rather than a when-to-use vs alternatives rule. No exclusions or alternative tools are named, leaving usage implied by the verb.

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