check_ending

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

readOnlyHint=true already establishes this is a safe read, so the bar is lower. The description still adds real behavioral context: the specific 16-second window plus export tail it renders, that it measures level, that it also reports song length, and how region changes the target. It stops short of disclosing cost/thresholds or whether the render is a full offline bounce.

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?

Every clause is front-loaded and informative: the core check comes first, the detection list second, the length report third, and the region override last. There is no filler or restated name/title.

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 helpfully enumerates the endings it detects and notes it reports song length, which approximates the return content, and annotations cover safety. What is still missing is any indication of thresholds or pass/fail semantics (how quiet is 'too quiet'), which matters for acting on the result.

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 both tail_seconds and region are already fully documented in the schema. The description's 'plus the export tail' and 'with region, checks that region instead' essentially restate those schema entries rather than adding new meaning, so this lands at the baseline 3.

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 specific verb and resource ('checks how the song ends') and goes further by naming the exact mechanism (renders the last 16 seconds plus export tail, measures level) and the conditions it detects (fade-out, quiet/silent end, tail cut mid-ring, lingering stinger). This clearly separates it from generic analysis siblings like analyze_audio or check_tuning.

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?

Usage is only implied: the description ties the check to 'how it will be used', and the kind enum in the schema supplies the use-case framing (continuous/ending/stinger). There is no explicit when-to-use statement, no mention of when this check should precede an export or be skipped, and no named alternative tool.

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