browser_snapshot

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

With no annotations present, the description carries the full behavioral disclosure burden. It honestly warns that refs go stale after DOM changes or navigation, which is a non-obvious and important behavior. It also describes the return concept (page structure with element refs) and tab targeting, providing meaningful behavioral context beyond the bare operation.

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 compact and front-loaded: purpose first, then usage guidance, then the critical stale-ref warning, then the tabId detail. The 'IMPORTANT' flag draws attention to the most safety-relevant behavior. No sentence is wasted.

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?

This is a relatively simple tool with only two optional parameters and no output schema. The description covers what it returns, when to use it, the main caveat, and tab targeting. It doesn't over-explain, and it provides enough context for an agent to invoke it correctly in most workflows.

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 schema already documents both parameters. The description adds context for tabId by mentioning tab targeting, but doesn't elaborate on agentId's routing semantics beyond what the schema states. This matches the baseline for fully documented parameters.

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 states a specific verb and resource ('Capture accessibility snapshot of a page') and clarifies the key output ('page structure with element refs for interaction'). It also explicitly distinguishes itself from screenshots, so an agent can tell it apart from sibling tools like browser_take_screenshot.

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 guidance to use this instead of screenshots when locating elements to click/type, and includes a critical staleness warning with a concrete directive to re-snapshot after DOM changes or navigation. It doesn't enumerate all alternative tools or exclusion cases, but the primary decision point is well covered.

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