barevalue_validateCheck an audio file at a URL before ordering: confirms it can be downloaded, measures its length and checks it is speech and not music or silence. Nothing is charged.
| Name | Required | Description | Default |
|---|---|---|---|
| api_key | No | Barevalue API key (bv_sk_...). Get one with barevalue_register. Omit when the connection already sends an Authorization: Bearer header. | |
| file_url | Yes | Direct, publicly downloadable URL of the audio file |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds genuinely new behavioral context: 'Nothing is charged,' which the annotations cannot express, plus a concrete account of what work the check performs. It omits what a failed check returns (error vs. verdict), which is the remaining gap.
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 that front-loads the action, then lists the three checks, then closes with the cost reassurance. No filler, no repetition of the 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?
No output schema exists, so the description must carry the return-value burden; it does so partially by naming what is measured (length, speech/music/silence), but never states the shape of the result or how a negative verdict is surfaced. For a two-parameter pre-check tool with full schema coverage and annotations, this is nearly 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?
Schema description coverage is 100%, and both parameters (api_key, file_url) carry their own descriptions including the Bearer-header fallback and the 'publicly downloadable' constraint. The description only echoes the URL notion, adding nothing beyond the schema, so the baseline 3 applies.
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?
States a concrete verb and resource (check an audio file at a URL) and then enumerates exactly what the check covers: downloadability, length, and speech-vs-music/silence classification. The phrase 'before ordering' implicitly separates it from barevalue_submit_url, so an agent can route between the two without opening schemas.
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?
Gives clear context for when to call it ('before ordering'), which frames it as a pre-flight gate ahead of the submit step. It stops short of naming barevalue_submit_url as the alternative or stating when a check is unnecessary (e.g., already-known-good URLs), so it is clear but not exhaustive.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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