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

Annotations already declare readOnlyHint=true, non-destructive and closed-world, so the safety profile is covered elsewhere. The description contributes the "(offline)" signal, which usefully implies synchronous local analysis rather than a render/job pipeline. It says nothing about cost on long files, caching, or failure behavior for silent/corrupt media.

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 sentence fragment with the measured quantities front-loaded and zero filler. It is terse to the point of being noun-phrase-only, but every token conveys information.

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?

With no output schema, the description usefully doubles as a return-value summary by listing the four metrics produced. For a two-parameter read-only analysis tool with fully documented parameters, that covers what an agent needs to call and interpret it; the missing piece is disambiguation from neighboring audio-inspection tools.

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 100% — both `project` and `media` carry their own descriptions, including the helpful pointer to the timeline.tsx header for media identification. The description adds nothing beyond the schema, so the baseline of 3 applies rather than a penalty.

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 names a specific resource (a media file) and enumerates exactly which measurements are produced: integrated LUFS, loudness range, true peak, mean/max volume. That is far more informative than a restatement of the title. It stops short of distinguishing itself from adjacent analysis siblings such as probe_media, waveform_levels, or detect_silence.

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?

There is no statement of when to reach for this tool versus probe_media or waveform_levels, which likely report overlapping audio characteristics. The only contextual hint is the parenthetical "(offline)", which suggests local computation rather than a queued job, but that is left for 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.