start_bridge

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

With no annotations, the description carries the full behavioral burden, and it does disclose one important trait: the external dependency on a separately started WebDriverAgent process. It says nothing about timeout behavior, failure modes, or whether a connection is cached/reused, and the return format is covered by the output schema.

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?

A single front-loaded sentence with no filler, and the critical prerequisite is placed immediately after the purpose. It is arguably too terse for a connection tool, but nothing is wasted.

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?

An output schema and full schema coverage mean return values and parameters need not be explained. Still, for a tool whose whole job is verifying an external connection, the description omits what a successful versus failed check means and whether the bridge must be re-established, leaving a meaningful gap.

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 100%, so host, port, and device_id are already documented in the schema. The description adds no parameter-level detail beyond what the schema provides, which is the expected baseline when the schema does the heavy lifting.

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 concrete verb and resource ("Check WebDriverAgent connection"), which is specific enough to be understood. However, it conflicts with the tool name start_bridge, which implies establishing a bridge rather than verifying one, leaving the agent unsure whether this tool connects or merely probes. It also does not distinguish itself from sibling session/lifecycle tools like reset_session or list_devices.

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 parenthetical prerequisite ("WDA must be running separately via xcodebuild") gives useful context about when this call can succeed, implying it is a pre-flight check. But there is no explicit statement of when to call it versus alternatives, and no indication of what to do when the check fails.

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