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

Annotations already indicate this is a non-read-only, non-idempotent, non-destructive operation. The description adds the policy that projects should not be created speculatively and explains that aliases support future fuzzy matching. It does not disclose return values or post-creation effects, but the annotations cover the core safety profile and no contradiction exists.

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 focused sentences, with the most important usage condition front-loaded. Every sentence adds value: trigger condition, alias purpose, and the 'do not create speculatively' guardrail. No filler or repetition.

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 straightforward creation tool with five parameters and no output schema, the description provides enough context for correct invocation: when to call it, required confirmation, and alias behavior. Parameter details are left to the schema, which is acceptable here. A minor gap is that no return value is described, but the low complexity keeps this from being a significant issue.

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?

The description adds meaningful context for aliases, explaining their role in future fuzzy matching, and ties the rate parameter to user intent. The schema already documents rate, client, and billable_default reasonably well. With 60% schema coverage, the description compensates for the most non-obvious parameters.

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 clearly identifies the action ('create a project') and the specific resource involved, while also stating the exact triggering conditions: the user names a project that does not exist and confirms creation. This differentiates it from related workspace tools like create_client and list_projects.

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 strong guidance on when to use the tool: only after user confirmation and for projects that do not yet exist. It also warns against speculative creation. However, it does not explicitly name alternative tools for existing projects or client creation, so the when-not-to-use guidance is present but not fully tied to sibling tools.

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