stagehand_session_create

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

With no annotations provided, the description carries the full burden. It discloses the default backend (local Playwright), the option to use cloud, and the side effect of setting the session as active. However, it does not mention error conditions, session reuse behavior, or return values.

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 two sentences, front-loaded with the action, and every sentence provides useful information without waste. It is appropriately sized for the tool's simplicity.

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?

The tool has 4 optional parameters and no output schema. The description covers the core behavior and the main configuration option, and the schema covers all parameters. However, the description does not mention what the tool returns or the behavior when reusing a sessionId, which may be necessary for an agent to use the tool correctly in all cases.

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 input schema has 100% coverage, so the baseline is 3. The description explicitly mentions the cloud parameter and its default, but does not add meaning to browserWidth or browserHeight beyond the schema. Overall, the description adds minimal value over the schema.

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 uses a specific verb 'Create' and a specific resource 'browser session', and also states that the session is set as active. This clearly distinguishes it from sibling tools like stagehand_session_close, which is for closing 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?

The description implies usage for creating a session but does not explicitly state when to use this tool versus alternatives. It provides configuration guidance (local vs cloud) but no exclusion criteria or references to alternative tools.

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