Manage debugger watches

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

With no annotations, the description carries the full burden of behavioral disclosure. It lists the operations but does not explain side effects, prerequisites (e.g., an active session), or what happens when clearing all watches. This is insufficient for a mutating tool.

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, front-loaded sentence that efficiently lists the five supported operations. 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?

Given six parameters and no annotations or output schema, the description is too minimal to guide correct invocation. It lacks details on how actions map to parameters, which are essential for an agent to use the 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?

The description adds no direct parameter information, and schema coverage is 0%. It only hints at 'expression' and the action list maps to the action enum, but parameters like watchId, callFrameId, and targetSessionId remain unexplained, failing to compensate for the coverage gap.

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 manages watch expressions with a specific list of actions (add, remove, clear, list, evaluate). This distinguishes it from sibling debugger tools like breakpoint or debugger_evaluate, which focus on different concerns.

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 phrase 'on a global or paused frame' provides clear context about when to use this tool. However, it does not explicitly mention exclusions or alternative tools, so it lacks the explicit when/not guidance that would merit a 5.

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