fusion_get_comp_count

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

The readOnlyHint annotation already establishes this as a safe read operation, and the description does not contradict it. However, it adds no extra behavioral context such as behavior on missing items, edge cases, or return format specifics. With annotations present, this meets the minimum viable standard.

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 that conveys the essential purpose with zero wasted words. It is appropriately sized for the tool's simplicity.

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 is simple, has full schema coverage, an output schema (per context signals), and a readOnly annotation. The description sufficiently covers what the tool does without needing to explain return values, as the output schema exists. No pending questions about the tool's behavior remain unaddressed.

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 all three parameters (item_name, track_type, track_index), so the schema carries the full burden. The description adds no parameter-level detail beyond what the schema already provides, maintaining the baseline score.

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 states the tool returns the number of Fusion compositions on a timeline item, using a specific verb ("Return the number") and resource ("Fusion compositions on a timeline item"). It differentiates from sibling tools like fusion_get_comp_names and fusion_get_comp by focusing on the count.

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?

No explicit guidance is given on when to use this tool versus alternatives, but the purpose is straightforwardly implied by the name and description—use it when you need the count of compositions. It lacks explicit exclusions or alternative recommendations, placing it at the 'implied usage' level.

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