browser_open

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses a significant side effect (a few hundred MB download on first use) and an authentication prerequisite (Discord sign-in for hub_save). It does not detail all possible behaviors, but for a 0-parameter browser open action it is transparent enough.

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 compact sentences. The first front-loads the action and resource; the second packs two important behavioral caveats. No filler or redundancy.

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 low-complexity, zero-parameter tool with no output schema, the description is complete. It explains what the tool does, its side effects, and an authentication prerequisite connected to a sibling tool. Nothing essential for an agent to invoke it correctly is missing.

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, so the baseline is 4. The description adds no parameter semantics, but none are needed; the schema already fully covers an empty parameter set.

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 ('Open (or focus)') and a specific resource ('the builder in the MCP's own Chromium window'). The verb-plus-resource pairing clearly distinguishes it from sibling browser_close and other browser operations.

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?

Provides clear context for when it matters: the first use downloads Chromium, and a one-time Discord sign-in enables hub_save. It does not explicitly list exclusions or alternatives, but the zero-parameter scope and 'or focus' phrasing make the intended usage context reasonably clear.

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