Probe media file

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

Annotations already declare read-only, idempotent, closed-world behavior, so the description is not required to prove safety. It adds real behavioral value beyond that: URL inputs are refused, and crucially 'probing reads headers and does not prove that every frame decodes,' which warns the agent against over-trusting a successful probe.

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?

Three sentences, front-loaded with purpose, then constraints, then the important caveat. Every clause carries information an agent needs; nothing is padding.

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 read tool with an output schema, this covers what matters: inputs, scope limits, and the interpretation caveat. It does not say what happens on a missing/unreadable file (error shape) or whether the probe is expensive for large files, both minor gaps here.

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?

There is a single parameter with 100% schema description coverage, and the schema already states 'Absolute path of a local media file.' The description's '(absolute path)' restates rather than extends that, so this is the baseline case where the schema does the work.

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+resource ('Check one local media file') and enumerates exactly what comes back: duration, streams, codecs, dimensions, rational frame rate, sample rate, channels, rotation. That output list distinguishes it from siblings like list_project_media or get_timeline, which operate on collections rather than a single file.

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 conditions are clear and concrete: one file only, absolute path required, local files only, URLs refused. It does not explicitly route the agent to a sibling (e.g., 'use list_project_media to discover paths first'), so the alternative-selection guidance is implicit rather than stated.

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