snapshot

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

With no annotations provided, the description carries full burden and adds valuable behavioral context beyond the input schema. It discloses that refs become stale after navigation, explains the token reduction benefit of compression (~90%), and describes how refs are used with execute tool. It doesn't mention rate limits, authentication needs, or error conditions, but provides substantial operational guidance for a tool with no 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 appropriately sized and well-structured. It front-loads the core purpose, then provides return format details, usage notes, and parameter explanations in logical sections. Every sentence adds value: the first states purpose, the next two explain ref usage, and the parameter section clarifies options with practical benefits. No wasted words or redundancy.

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 3 parameters with 100% schema coverage and no output schema, the description provides good contextual completeness. It explains the return format (DOM tree with refs), ref usage patterns, navigation constraints, and practical benefits of parameters. For a tool with no annotations and no output schema, it covers most essential context, though it could mention error cases or performance characteristics more explicitly.

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 description coverage is 100%, so the schema already documents all parameters thoroughly. The description adds minimal value beyond the schema: it restates the purpose of 'search' and 'showDiff' similarly to the schema, and adds the token reduction percentage for 'compress'. Since the schema does heavy lifting, baseline 3 is appropriate with marginal description enhancement.

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: 'Get compressed accessibility snapshot with ref IDs.' It specifies the verb ('Get'), resource ('compressed accessibility snapshot'), and key output characteristic ('with ref IDs'). It distinguishes from siblings by focusing on accessibility snapshots with ref IDs, unlike browser_execute (execution), browser_network_requests (network data), browser_search_snapshot (search-focused), or screenshot (visual capture).

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 provides clear context for when to use the tool: 'Call again after navigation (refs become stale)' and implies usage for tracking page updates via showDiff. However, it doesn't explicitly state when NOT to use this tool or name specific alternatives among siblings (e.g., when to use browser_search_snapshot instead). The guidance is helpful but lacks explicit exclusions or named alternatives.

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