ffmpeg__probe_media

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

With no annotations provided, the description carries the behavioral disclosure burden. It reveals the tool returns ffprobe JSON output to stdout containing streams and format information, which is a key behavioral trait. It does not mention failure conditions or side effects, but for a read-only probe operation this is adequate.

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?

The description is compact and uses a structured @remarks/@param format that is easy to parse. There is slight redundancy between the opening sentence ('return full metadata as JSON') and the @remarks line ('Returns ffprobe JSON output in stdout'), but it is not verbose and every line earns its place.

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 simple probe tool with no output schema, the description covers the essential aspects: what it does, the parameters, and the return format. It omits details like error handling or file accessibility, but these are not critical for such a straightforward operation. The absence of annotations is offset by the parameter and output disclosures.

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?

The schema provides zero description coverage, but the description fully compensates with explicit @param lines: input_path is defined as the source media file path, stream_type explains filtering with default 'all' and valid values 'video' or 'audio', and __mcp_response_mode clarifies the 'content' default and 'structuredContent' option. This adds significant meaning beyond the bare schema types.

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 opens with a specific verb and resource: 'Probe a media file and return full metadata as JSON using ffprobe.' This clearly states what the tool does and its output format. The use of 'probe' and 'metadata' distinguishes it from sibling ffmpeg tools that process or transform media rather than inspect it.

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 implied: use this tool when you need to inspect a media file's metadata. There is no explicit 'when to use vs alternatives' or exclusionary guidance, but the purpose is clear enough that an agent would naturally select it for probing. No sibling tool performs the same role, so explicit alternatives are not necessary.

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