model_report_usage

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

Without annotations, the description carries the burden of behavioral disclosure. It explicitly declares 'Read-only' and details the classification logic, including the three categories and the types of bindings it detects. This adds significant transparency beyond the basic read-only hint, though it omits details like error handling or performance implications.

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 dense but well-organized, front-loading the core purpose and then breaking down the classification. Every sentence provides useful detail, though it could be slightly more concise by trimming the rhetorical phrase 'the bindings naive scanners miss' without losing value.

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 tool with no output schema, the description fully explains what the tool does, the inputs required, the classification categories, and its distinction from a sibling tool. It gives the agent everything it needs to understand the tool's behavior and output expectations, including the read-only nature.

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 coverage is 100% with both parameters documented. The description adds meaning by explaining how reportSource is a join key ('a reportSessionId from open_report, a pbirSessionId from read_pbir, or a path to a PBIR .pbix/PBIP folder') and clarifies the relationship between sessionId and reportSource. This goes beyond the schema's basic field descriptions.

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's purpose: 'CROSS-LAYER usage analysis' that joins a model with a report and classifies every field as DIRECT, INDIRECT, or UNUSED. It differentiates from siblings by emphasizing it can produce the UNUSED shortlist that 'find_unused (model-only) cannot produce'.

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 implies when to use this tool: for cross-layer analysis requiring the join of a live model and a report. It explicitly references the alternative find_unused and notes this tool's advantage, providing clear context. It doesn't state when not to use it, but the context is strong enough to guide selection.

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