launch_dev_client

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

With no annotations, the description carries the full burden and does well: it discloses the network dependency on adb_reverse, the failure mode when the device cannot reach Metro, and that the action is performed by opening a deep link. It does not say what is reported on success or what happens if no app claims the scheme, so it stops short of full transparency.

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 action is front-loaded in the first sentence, followed by the prerequisite and the alternative, each in its own short statement. No sentence is redundant and the ordering matches decision order for an agent.

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 five-parameter tool with no annotations and no output schema, the description covers the critical operational context: how the deep link is formed, the network prerequisite, the fallback behavior, and the sibling alternative. It omits the return/error surface, which is the only notable 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 all five parameters are already documented, establishing a baseline of 3. The description restates the scheme and default host/port and ties host semantics to the adb_reverse prerequisite, but adds no syntax or format 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?

Names a specific verb and resource (launch an Expo dev build at a Metro server) and explains the mechanism (builds the expo-development-client deep link and opens it). It explicitly distinguishes itself from the sibling open_url for plain Expo Go, so an agent can pick correctly without opening the schema.

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?

Gives an explicit prerequisite (run adb_reverse {device_port: 8081} first), explains the consequence of skipping it (falls back to the embedded bundle), and names the alternative tool plus the condition that selects it (open_url with exp:// for Expo Go).

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