vibeside_eval

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

With no annotations, the description carries the full burden and falls short: it doesn't say whether the expression runs in the page's main world or an isolated one, whether it can mutate the page, whether evaluation is awaited (async/promise resolution), or what errors look like. 'In the browser context' is the only behavioral clue.

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?

One front-loaded sentence with no filler; the verb and resource come first. It is efficient, though the extreme brevity leaves behavioral gaps that a slightly longer description could have closed.

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 an eval tool with no annotations and no output schema, the agent needs to know the return shape (does it return the evaluated value, serialized how?), error behavior, and side-effect potential. None of that is covered, leaving the definition under-specified for the operation's inherent risk.

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% for the single 'expression' parameter, so the schema already documents type and meaning. The description's phrase 'arbitrary JavaScript expression' reinforces but adds no syntax, format, or constraint detail beyond 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 gives a specific verb ('Evaluate') and resource ('an arbitrary JavaScript expression') plus the execution context ('browser context'). No sibling tool does expression evaluation, so the agent can identify it, though the description never explicitly states that uniqueness.

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?

There is no guidance on when to reach for this tool versus siblings like vibeside_dom_snapshot, vibeside_inspect_storage, or vibeside_inspect_component, which also expose page state. No mention of prerequisites (page must be connected/navigated first) or when-not-to-use.

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