set_status_bar

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

The description discloses key behavioral traits: it uses SystemUI demo mode, sets fixed clock and battery, hides notification icons by default, and notes 'best-effort' for notification icon support. Since no annotations are provided, the description carries the full burden and does so well, though it could mention that changes are immediately visible or persistent behavior after tool completion.

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 description is a single, well-structured paragraph of three sentences. Every sentence adds distinct value: purpose and primary behavior, optional parameter guidance, and restoration call. No redundancy or filler.

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 10 parameters, no output schema, and no annotations, the description comprehensively covers the tool's purpose, behavior, and parameter guidelines. However, it could explicitly state the return value (e.g., success/failure) or side effects (e.g., device UI changes instantly), but the context is sufficient for an agent to use the tool correctly.

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 the baseline is 3. The description adds value beyond the schema by grouping parameters conceptually (e.g., 'battery as 0-100 (shown unplugged)' gives context not in the schema) and explaining the high-level behavior (no notification icons by default). This justifies a 4.

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 the tool pins a clean status bar via SystemUI demo mode for screenshot documentation. It specifies the verb 'pin', the resource 'status bar (via SystemUI demo mode)', and the purpose 'so screenshots for docs don't leak the wall clock or a random signal state', which differentiates it from other device-setting tools.

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 explains when to use the tool (for clean screenshots) and explicitly mentions how to restore ('Call with enabled=false to restore the live bar'). However, it does not provide explicit alternatives or when-not-to-use guidance, though the sibling tools are diverse and none appear to serve the same purpose, so the lack of exclusions is acceptable.

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