break_on_xhr

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the tool sets a breakpoint that triggers on URL matches, but it does not describe what happens when triggered (e.g., pauses execution, logs details), potential side effects, permission requirements, or error handling. This leaves significant gaps for a mutation tool with no annotation coverage.

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, well-structured sentence that efficiently conveys the tool's purpose and parameter usage without any redundant information. It is front-loaded and appropriately sized, with every word earning its place.

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 (a mutation tool for debugging), no annotations, 1 parameter with low schema coverage, and an output schema (which reduces need to describe return values), the description is somewhat complete but lacks details on behavioral outcomes, error cases, and integration with sibling tools. It provides a basic understanding but leaves gaps for effective use.

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 input schema has 1 parameter with 0% description coverage, and the description adds meaning by specifying that the 'url' parameter is a string used to match against XHR/Fetch request URLs. However, it does not provide details on format (e.g., substring matching, case sensitivity) or examples, so it partially compensates but does not fully cover the parameter semantics beyond the basic schema.

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 with a specific verb ('Sets a breakpoint') and resource ('XHR/Fetch request URL'), and it distinguishes from siblings like 'remove_xhr_breakpoint' (which removes breakpoints) and 'set_breakpoint_on_text' (which sets breakpoints on text in scripts). It precisely defines the trigger condition ('when an XHR/Fetch request URL contains the specified string').

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 usage for debugging XHR/Fetch requests by setting breakpoints based on URL patterns, but it does not explicitly state when to use this tool versus alternatives like 'list_breakpoints' (to view breakpoints) or 'remove_xhr_breakpoint' (to remove such breakpoints). It provides context but lacks explicit guidance on exclusions or prerequisites.

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