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 still adds real context: it is a pre-flight check performed before ordering, and "Nothing is charged" explicitly confirms no side effects or billing, reinforcing the annotations rather than merely repeating them.

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 sentences, zero waste, with the core purpose front-loaded and the no-charge guarantee placed last as a clarifying note. Every clause carries distinct information: what it reports, the scoping to a given length, and the pre-order, no-cost nature.

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 carries the burden of conveying what comes back. It says the estimate covers usage and account coverage, but does not describe the shape of the result (e.g. units consumed, a boolean affordability verdict, or a shortfall figure), leaving the agent to discover the return format empirically.

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 api_key and duration_minutes are fully documented in the schema (including the 1-60 range and the bv_sk_/Authorization substitution). The description adds no syntax or format detail beyond the schema, so the baseline of 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 specific verb and resource: it reports the resource consumption of an AI podcast edit at a given length and whether the account can cover it. This clearly separates it from the ordering/upload tools, but it never explicitly contrasts with the plausibly-overlapping sibling barevalue_pricing, so differentiation is only implicit.

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?

"before any order is placed" gives an explicit temporal context that tells the agent when this tool belongs in a workflow. It stops short of naming alternatives or exclusions (e.g. when to prefer barevalue_pricing instead), but the pre-order framing is clear rather than merely implied.

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