adb_mirror_start

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

With no annotations, the description must disclose behavioral traits. It discloses windowed/headless modes, the need for scrcpy, and the session limit. However, it does not describe whether the tool blocks, returns immediately, or what happens to existing sessions, leaving some behavioral gaps.

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?

Three sentences with 29 words, front-loaded with purpose, prerequisite, then modes and limitation. No redundancy and every sentence adds value.

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?

Given 8 parameters and no output schema or annotations, the description covers purpose, prerequisite, modes, and a limitation. It lacks mention of return value or asynchronous behavior, but is largely complete for a start-action tool.

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 baseline is 3. The description adds context about headless mode being useful with recording and states modes generally, but does not deeply elaborate on each parameter beyond what the schema already provides.

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 clearly states that the tool starts live screen mirroring for a device using scrcpy, mentioning supported modes and a key limitation (one session per device). This distinguishes it from screenshot and recording tools among siblings.

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 specifies the prerequisite (scrcpy installed and on PATH) and notes the one-session-per-device constraint, providing useful context. However, it does not explicitly exclude alternatives like adb_screencap or adb_screenrecord_start, nor provide when-not-to-use guidance.

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