List recent browser sessions

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

Annotations indicate readOnlyHint=true; description confirms read-only listing. Adds behavioral details: free-text field clipping (origin 100, url 300, title 200 chars) and origin scoping under client roots. No contradiction. Provides useful behavioral context 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?

Extremely concise and well-structured: starts with action, then output format, then key behavioral notes, then usage recommendation. Every sentence is informative without 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?

No output schema, but description sufficiently explains return format and fields. Covers key behaviors (clipping, scoping) and positions the tool in the workflow. Complete for a read-only list tool.

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 baseline is 3. Description adds minor value: clarifies that omitting origin means 'across all recorded origins (subject to client roots scoping)' and that limit defaults to 10 with newest-first ordering.

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 identifies the tool's purpose: listing browser sessions, newest first. It specifies the output format (compact JSON rows with fields) and distinguishes itself from sibling tools by positioning as the entry point for session-related tools.

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?

Provides explicit guidance: start here to get a sessionId, then call get_session_summary. Mentions origin filtering and client-root scoping, suggesting when to use filters. Lacks explicit when-not or alternative conditions, but context is clear.

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