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

Annotations already declare readOnlyHint=true, so the read-only nature is covered. The description adds the return fields but does not disclose additional behavioral aspects such as pagination, rate limits, authentication requirements, or side effects. Since the bar is lower with annotations, a score of 3 is appropriate—the description is consistent and does not contradict annotations, but it adds minimal extra behavioral context.

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 a single sentence that front-loads the core action and includes the return fields in parentheses. There is zero wasted text, and the information is presented in an efficient, scannable manner. It is appropriately concise for a simple list tool.

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 simple list operation with one optional parameter and no output schema, the description covers the essential purpose and return fields. It implies the scope ('you can build into') and provides the output structure. It does not mention pagination or ordering, but these are minor for a straightforward list call. The description is sufficiently complete for an agent to invoke it correctly.

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% for the single parameter 'limit' (Max results, default 50). The description does not add any meaning beyond what the schema provides. Given high schema coverage, the baseline of 3 is correct—the description is not required to compensate, and it does not.

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 clear verb and resource: 'List projects you can build into' and enumerates the returned fields (uuid, name, schema_namespace, live_url). It distinguishes itself from sibling tools like build_get_project (which likely retrieves a single project) and build_list_bound_schemas (which lists schemas) by clarifying the scope as buildable projects. The purpose is unambiguous and specific.

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 provides no guidance on when to use this tool versus alternatives. It does not mention build_get_project for details, build_create_project for creation, or any exclusions. While the purpose implies listing projects, there is no explicit when-to-use or when-not-to-use guidance, which is a gap given the large sibling set.

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