list_sessions

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

Annotations already declare this as a read-only, idempotent, non-destructive, closed-world operation. The description adds useful workflow guidance about explicitly choosing a browser_session_id for other tools, but does not describe the return shape, empty results, or whether multiple sessions may be listed.

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?

Two short sentences, front-loaded with the action and resource. Every sentence adds usable information, with no filler or redundant restatement.

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 zero-parameter list tool with rich read-only annotations and no output schema, the description is nearly complete. It identifies the resource and explains how the result is used, though it could clarify the return shape 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?

The tool has zero parameters and full schema coverage, so there are no parameter semantics to explain. The description appropriately focuses on the tool’s purpose and prerequisite usage rather than redundant parameter details.

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?

States a specific verb and resource: "List paired browser tabs." This clearly identifies the tool’s function and distinguishes it from the mutation-oriented siblings, though it uses "browser tabs" rather than explicitly saying "sessions."

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?

Adds clear workflow context by saying to choose a browser_session_id for other tools, which implies this tool is the prerequisite for session-scoped operations. It does not state exclusions or alternatives, but none are obviously needed for a zero-parameter list tool.

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