chrome_scroll_jank_summary

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, which the description reinforces ('Read-only'). It adds details like operating on the loaded trace, empty result meaning (clean trace or no scrolls), and output metadata (row_count, truncated flags). No contradictions.

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?

Concise yet comprehensive, using clear sections and bullet-like lists. Every sentence adds value, and the structure is front-loaded with key info. No wasted words.

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 3 parameters and no output schema, the description thoroughly explains output format, metadata, and edge cases (empty results, truncation). It fully compensates for lack of output schema.

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%; the description adds context beyond the schema, such as default limit (100), cap (5000), and max_string_len purpose. This elevates it above the baseline 3.

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 summarizes the worst scroll jank frames from a Chrome trace, listing specific output columns. It distinguishes itself from siblings like `execute_sql` and other Chrome summary tools, providing a specific verb+resource.

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?

Explicit guidance on when to use (investigating jank, finding regressions) and when not to (non-Chrome traces). Also suggests an alternative (`execute_sql`) for custom filters, leaving no ambiguity.

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