Take heap snapshot

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

The description discloses important behavioral traits beyond the annotations: writes a raw .heapsnapshot file for DevTools, can be hundreds of megabytes and take several seconds on heavy pages, and the response reports the file size. This adds value not present in the minimal annotation hints.

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 four sentences, each earning its place: purpose, output format, workflow, and performance/response detail. It is front-loaded with the main purpose and contains no redundant or extraneous text.

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 with one parameter and an output schema. The description covers the workflow, file format, performance, and response. No critical contextual information is missing for an agent to invoke this tool effectively.

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?

The schema description for 'file_path' already covers the parameter fully (local path, open in DevTools). The tool description adds no additional parameter-specific semantics beyond what the schema provides, so a baseline score of 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?

Description uses a specific verb ('Capture') and clearly identifies the resource ('V8 heap snapshot of the page') with an explicit purpose ('for memory-leak debugging'). It distinguishes from sibling tools like take_snapshot (which likely captures a DOM or screen snapshot).

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 provides clear context by specifying the use case (memory-leak debugging) and the typical workflow (two snapshots around a suspect interaction). It does not explicitly mention alternatives or when-not-to-use, but the context is sufficient for an agent to decide when this tool is appropriate.

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