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

Annotations already establish the read-only, non-destructive nature, but the description adds important context beyond them: url survives redeploys unless the app address changes, works for public or restricted projects, and machine_url must never be exposed because restricted projects refuse viewers there. This is valuable safety and output-handling guidance.

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?

The description is four focused sentences: it front-loads what is listed, then states the primary use, then gives safe output guidance. Every sentence adds distinct value without waste.

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?

With zero input parameters and an output schema already present, the description supplies what is needed: list scope, key returned fields, usage for project_id lookup, and explicit url/machine_url safety guidance. Nothing essential for correct invocation is missing.

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 tool has zero parameters and the input schema is empty, so there is no parameter behavior for the description to supplement. The baseline for zero-parameter tools is 4.

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 uses a specific verb and resource ("List the caller's spawnpoint projects") and enumerates the returned fields, including the project_id. It also distinguishes the tool's core retrieval purpose by saying it is used to find a project_id for a named project.

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?

It gives clear usage context: find the project_id of a project the user names, and show the user the shareable url. It does not explicitly compare against alternatives such as get_project or list_team_space, so it falls short of full when/when-not guidance.

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