quest_performance

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

In the absence of annotations, the description takes on the responsibility of disclosing behavior. It gives useful context such as the battery drain sign convention (negative = discharging) and lists the snapshot contents, but it does not explicitly state whether this is a read-only operation, what the output format is, or whether device_id is required.

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, front-loaded sentence that efficiently communicates the core function and the list of returned metrics. There is no redundant filler, making it easy to parse quickly.

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?

The tool has no annotations and no output schema, so the description is the sole source of operational context. It enumerates the metrics returned, which is helpful, but it leaves critical gaps: it doesn't specify the output structure (e.g., units, JSON layout), the meaning or optionality of device_id, or the behavioral safety profile (read-only vs. side effects). For a tool with such minimal structured context, this is partially complete.

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?

The single parameter device_id is completely undocumented in both the input schema (no description) and the tool description (not mentioned). With 0% schema description coverage, the description fails to compensate, leaving agents to guess whether device_id is required, what values are valid, or what the default null means.

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 uses the specific verb 'Get' and resource 'performance snapshot', and enumerates specific metrics (CPU, memory, thermal status, battery, foreground app, top processes). This clearly defines the tool's function, but it does not explicitly differentiate it from related sibling tools like quest_thermal or quest_monitor, which may offer overlapping subsets of these metrics.

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 provides no information about when to use this tool versus the many siblings (quest_thermal, quest_monitor, quest_perf_session, etc.). There are no context cues, prerequisites, or exclusions, leaving the agent without guidance on tool selection.

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