Mark async recording timeline

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

Annotations already declare the safety profile (readOnlyHint=false, destructiveHint=false, non-idempotent), so the agent knows this is a non-destructive write. The description adds the 'offsetMs from record start' framing but omits behaviors like what happens if no recording is active, whether labels must be unique, or ordering guarantees.

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 the core action stated first and no wasted words. The trailing 'analyze/focus/logcat' reference is slightly loose (not exact tool names) but still compact and informative.

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 exists, so return values needn't be explained, and the simple mark operation is mostly covered. Still missing the operational prerequisite that a recording must be running and that recordId must originate from mobile_record_start, which matters for a 3-required-param write 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 coverage is 67%, with serial and label well described in the schema; recordId carries only a format/pattern. The description adds little param detail beyond clarifying label semantics implicitly via 'labeled timestamp'. The mention of 'offsetMs' refers to a computed value, not a parameter, so it doesn't clarify any input.

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 action ('Attach a labeled timestamp') plus the mechanism ('offsetMs from record start'), so an agent understands this records a timeline marker within an active recording. It doesn't explicitly name or contrast itself against siblings like mobile_record_start/stop, but the purpose is clearly distinguishable from them.

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?

'for later correlation with analyze/focus/logcat' implies why you'd use it, giving implied usage context. However, it never states the key precondition (a recording must be active, recordId from mobile_record_start) or when-not to use it, leaving the agent to infer.

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