ghost_tab_eval

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

The description does add one useful behavioral trait: it awaits promises before returning the value. However, there are no annotations, so the description carries the full burden, and it does not disclose potential side effects of executing arbitrary JavaScript, error behavior, serialization limits, or security implications. This is a significant gap for a code-execution tool.

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 one tight sentence with no filler. It front-loads the core action and then adds the important promise-awaiting detail parenthetically. Every word contributes meaning.

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 tool that evaluates arbitrary JavaScript, the description is too thin. With no output schema, no annotations, and 0% parameter coverage, the agent is left without guidance on return value formats, exception handling, side effects, or parameter semantics. The promise handling is helpful but not enough for safe and correct invocation.

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 0%, and the description only gives meaning to 'expression' (it is a JavaScript expression). The 'tab' and 'browser' parameters are left unexplained—no guidance on their formats, how to identify a tab, or whether browser is optional. The description does not compensate for the lack of parameter documentation.

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 states a specific verb ('Evaluate'), resource ('a JavaScript expression in the tab'), and outcome ('return its value'). This clearly distinguishes it from sibling tab tools like ghost_tab_navigate or ghost_tab_click, which do different operations. No ambiguity about what the tool does.

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 the tool is used when you need to run JavaScript inside a tab and get a result, but it does not explicitly state when to prefer this over alternatives such as ghost_query, ghost_run, or ghost_tab_describe. No exclusions or alternative-routing guidance is provided.

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