audio_timeline

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful behavior beyond that: it streams the file, so it works on recordings of any length without loading everything into memory. It stops short of describing pagination or sparkline resolution.

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?

Two tightly written sentences, front-loaded with what the tool returns and followed by the operational constraint. Nothing is redundant and every clause adds 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 and 0% parameter coverage across four parameters, the description should do more work. It usefully sketches the return shape (per-segment RMS, peak, brightness, sparkline), but leaves the start/end windowing semantics undocumented, which matters for a tool that claims to handle files of any length.

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 0%, so the description carries the burden for path, start, end, and segments. 'Per-segment' loosely hints at the segments parameter, but start/end ranges (units, whether seconds or samples) and the default of 24 segments are never explained, leaving half the parameters ambiguous.

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 the resource (audio timeline) and enumerates the specific outputs (per-segment RMS, peak, brightness, loudness sparkline), which is far more informative than the bare name. It does not, however, contrast itself with the many audio siblings like audio_analyze, audio_info, or audio_events, so an agent must infer the distinction.

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?

It gives one concrete use case, 'use it to find where to zoom in', which implies the tool is for coarse temporal scanning rather than detailed analysis. There is no guidance on when to prefer audio_analyze or audio_events instead, and no exclusions, so usage remains largely implied.

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