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

Annotations already indicate the operation is mutating but not destructive. The description adds useful behavioral detail beyond annotations: only explicitly passed fields are changed化的, and statuses/labels are never affected. It doesn't cover permissions or error behavior, but for this simple update the core behavior is well disclosed.

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 deliver the purpose, the partial-update rule, and the alternative-tool routing with no filler. The most important constraint ('only touches name/description') appears early and is reinforced at the end.

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 3-parameter tool with full schema coverage locked, the description covers what the tool does, how partial updates work, and which alternatives to use. The only notable gap is not describing the response shape or invalid-projectId behavior, but given no output schema and the simple nature of the operation, this is a minor omission 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%, so the schema already documents projectId, name, and description. The description adds meaningful semantics by stating that omitted name/description fields are left unchangedched and clarifying that this tool does not modify status/label fields, which is value beyond the raw 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 names a specific verb ('Update') and a specific resource ('a standalone project'), then narrows the scope to 'name or description.' It explicitly says the tool 'only touches name/description,' which clearly separates it from siblings like update_standalone_status and update_standalone_label.

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 description gives explicit when-to-use guidance: use it for name/description changes, and use dedicated status/label tools for statuses or labels. It also clarifies partial-update behavior ('omit a field to leave it as-is'), helping the agent decide what parameters to pass.

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