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

Annotations already declare destructiveHint=true, idempotentHint=true, readOnlyHint=false, so the safety profile is largely covered. The description adds a real piece of context the annotations do not carry: the projects:write scope requirement. However, it never explains partial-update semantics (are omitted fields preserved or cleared?), which matters a lot for a destructive 16-field update.

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 no filler, and the identity/scoping statement is front-loaded ahead of the permission note. It is efficient, though arguably too terse for the size of the operation.

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 destructive, 16-parameter update with no output schema, the description omits essential context: whether this is a full replace or partial patch, how unspecified fields are treated, and whether any fields are immutable after creation. Annotations cover only the generic safety hints, so the description leaves significant gaps.

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 16 parameters, including the enum values, are already documented in the schema and the baseline is 3. The description adds nothing beyond 'by ID', which merely restates the required id parameter.

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 existing project') and adds the lookup key ('by ID'), so the agent knows exactly what entity is mutated. It does not differentiate itself from siblings such as create_project or the many update_project_* sub-resource tools, but the name plus the 'existing project' phrasing makes the target unambiguous.

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?

Usage is only implied: 'existing project' hints that create_project is for new projects and update_project_* variants are for sub-resources, but no alternative is named and no when-not condition is given. The 'Requires projects:write scope' clause is a useful prerequisite, which lifts it above pure silence.

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