debugger_set_breakpoint

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

With no annotations at all, the description carries the full disclosure burden, and it does so well. It reveals that URL substrings are resolved to exact scripts, original paths are translated through source maps, Chrome might fail to bind the breakpoint and the tool will report that honestly, and auto_resume affects whether the page stays frozen. The note that a paused execution is released after maxPauseMs regardless is especially valuable transparency.

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 three sentences with no filler. The core action and reporting promise are front-loaded, followed by the input-mode details and then the auto_resume guidance. Every sentence earns its place and contributes to correct invocation.

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 five parameters, no output schema, and no annotations, the description is nearly complete: input modes, failure honesty, and pause/resume behavior are all covered. The main omission is lack of explicit routing to sibling tools such as debugger_set_breakpoint_at_function or debugger_list_breakpoints, but the description plus a detailed input schema is enough for an agent to invoke this tool correctly.

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%, so the baseline is 3. The description adds real semantic value beyond the schema: it explains substring resolution behavior for url and the source-map translation for original pre-bundling paths. It also adds context for auto_resume beyond its schema description, clarifying the automation-driven scenario and the timeout release behavior.

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 opens with a specific verb and resource: 'Set a breakpoint' in Chrome. It also commits to a distinctive behavioral promise, 'report honestly whether Chrome could bind it,' which makes the tool's purpose concrete. The accepted input modes (script URL/substring vs. original source path) clearly separate this from the sibling debugger_set_breakpoint_at_function even without naming it.

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 gives explicit conditional guidance for the auto_resume parameter, telling the agent when to set it to true versus false and explaining the consequence of each choice. However, it does not explicitly say when to choose this tool over the function-based breakpoint sibling or the breakpoint-management siblings. That routing is only implied by the input-mode description, so the guidance is present but not fully explicit.

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