pbi_eval

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

Discloses key behaviors: evaluates JS, returns JSON-serialized result, and notably the 'best-effort textual guard' for access token rejection. However, does not mention potential side effects on page state or error handling.

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?

Two concise sentences with no redundant text. Front-loaded with 'Escape hatch' for immediate purpose recognition. Every line adds 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?

Given the tool's complexity (code evaluation) and lack of output schema, the description omits crucial context: what the JSON-serialized result contains, error behavior, and security implications beyond the token guard.

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?

With 0% schema description coverage, the description partially compensates by specifying the parameter is a 'function-body or arrow-fn string'. But lacks details on expected format, syntax rules, or limitations beyond the token guard.

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?

Clearly states it evaluates JavaScript code in the reportView page using specific verb 'evaluate' and resource 'function-body or arrow-fn string'. The 'escape hatch' label distinguishes it from other tools by implying low-level, unrestricted execution.

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?

Does not explicitly state when to use this tool versus siblings like pbi_run_code. Provides only a constraint (rejects powerBIAccessToken references) but no contextual guidance on preferred use cases.

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