audio_decode_vag_block

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

With no annotations, the description must carry the full behavioral burden, and it does add real substance: exact input size (16 bytes) and exact output cardinality and format (28 linear 16-bit PCM samples), which an agent could not infer otherwise. It says nothing about error handling for malformed hex, whether the block header/predictor/scale byte is parsed, or whether decoding is deterministic across blocks (state carried between blocks).

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?

One sentence, front-loaded with the action and resource, with zero redundant wording. The input size and output size/format are packed into the same clause rather than spread across filler text.

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?

For a one-parameter primitive with no output schema, the description supplies nearly everything needed to call it correctly, including the return value's size and sample format. The only missing piece is failure behavior on invalid or mis-sized hex input, plus whether block-to-block predictor state matters for producing correct audio.

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 the single parameter is already documented, which sets the baseline at 3. The description adds a modest constraint by fixing the expected length at 16 bytes, implying 32 hex characters, but it does not clarify accepted formatting (whitespace, 0x prefix, endianness of the block).

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 precise verb (decode) plus the exact resource (a 16-byte Sony PS2 VAG ADPCM block) and even the output shape (28 linear 16-bit PCM samples), which is far more specific than the name alone. It implicitly distinguishes itself from the file-level sibling audio_decode_file by scoping strictly to one block, but it never names that alternative or states the distinction explicitly.

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 when-to-use or when-not-to-use guidance. An agent cannot tell from the text whether this is the right tool for decoding a VAG stream (versus audio_decode_file or audio_inspect) or only for block-level work inside a decoding loop, and no prerequisites or alternatives are mentioned.

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