Variables

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

Annotations already mark the tool as read-only and non-destructive, and the description adds substantial behavioral detail: default 32-property preview, cursor pagination, overflow/已折叠 truncation markers, [Circular]/已回环 cycle markers, and scope omission behavior. This is exactly the kind of context agents need beyond annotations.

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 dense but well-organized, front-loading the core action and then efficiently covering preview behavior, expansion, scope limitations, and the paused-target requirement. Every sentence contributes actionable information without filler.

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 read-only inspection tool with optional parameters and no output schema, the description covers the critical behavior: what it inspects, how previews work, how to page/expand, scope omissions, and the paused-target precondition. An agent has enough context to select and invoke it 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?

All 7 parameters are documented in the schema, so the baseline is 3. The description adds value beyond the schema by explaining cursor paging, preview truncation behavior, expansion via objectId from previous results, and how includeGlobal/scopeIndex affect scope inclusion.

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 uses a specific verb and resource: 'Inspect locals/closures on a paused frame, or expand an objectId from a previous result.' This clearly distinguishes the tool from related siblings like debug_evaluate and debug_get_stack by describing exactly what it operates on.

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 clear context and conditions: it requires a paused target, and it explains that global/script scopes are omitted unless includeGlobal or scopeIndex is set. It does not explicitly name sibling alternatives or when-not conditions, but the intended usage is clear.

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