Select Browser Mode

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

No annotations exist, so the description carries the full burden, and it discloses meaningful behavior: connect uses the user's Chrome via a debug port, headless is an invisible Puppeteer instance that is always available, the setting persists for the session, and headless auto-selects when it is the only option. Missing error/fallback behavior when connect fails, which is the main residual gap.

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?

Front-loaded with the critical instruction ('CALL THIS FIRST'), and every sentence carries actionable content. Five sentences is slightly more than needed; the auto-select sentence could be merged with the mode definitions without losing information.

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 exists, so the description appropriately hints at the query return ('call without params to see what is available') and covers both invocation paths and the session-scoping behavior. It stops short of describing the returned shape or how a stale session default is reset, which for a stateful session tool would be useful.

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 baseline is 3, but the description goes beyond the enum by explaining the operational consequences of each value and clarifying that omitting mode performs a pure query rather than a set. That meaning is not inferable from the schema alone.

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 action (check available modes and set the session default) on a specific resource, and immediately distinguishes itself from all 38 sibling browser tools by being the mandatory first call. An agent can tell exactly what this does and where it sits in the workflow.

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?

Strong ordering guidance: 'CALL THIS FIRST before using any other browser tool,' plus explicit instructions for the query form (omit mode) and the configuration form (mode=headless/connect), and the auto-selection fallback. It lacks any when-not-to-use condition or failure-path guidance (e.g., what to do if connect is unavailable).

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