fcp_list_libraries

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

The annotations already establish that this is a safe read-only operation with openWorldHint=false, so the description does not need to repeat safety claims. It adds useful scope by clarifying that results include events and projects, but it does not describe filtering behavior, performance implications of details, or how "open" libraries are determined.

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 front-loaded sentence with no wasted words. It states the core action and scope immediately.

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?

The tool has a complete schema, an output schema, and read-only annotations, so the description does not need to explain return values or safety. It conveys the main inventory purpose and nested result shape, but it omits any mention of the optional library/event filters or the slower details behavior.

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 the schema already documents the event, details, and library parameters thoroughly. The description adds only a high-level indication that events and projects are included, without explaining the optional filters beyond what the schema provides; baseline 3 is appropriate.

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 gives a specific verb and resource: "List open libraries" and further specifies that each result includes events and projects. This clearly distinguishes it from single-project tools such as fcp_get_project, though it does not explicitly name a sibling as an alternative.

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 phrase "List open libraries with their events and projects" implies a discovery or inventory use case, but it does not state when to use this tool instead of alternatives like fcp_get_project or fcpxml_read. There are no exclusions or explicit guidance about prerequisites.

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