check_keyframesIdentify keyframe (I-frame) times and intervals in a video to verify fast seeking, exact trimming, and HLS or DASH streaming compatibility.
List the keyframe (I-frame) times of a video and check the keyframe interval. Use it to find out if a video seeks fast, trims at exact times, and streams well with HLS or DASH.
| Name | Required | Description | Default |
|---|---|---|---|
| input | Yes | A local file path or an http(s) URL of a video. |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations declare readOnlyHint=true, so safety is covered. The description adds the outcome-oriented purpose (seek speed, trimming, streaming), but doesn't disclose return format details like whether times are timestamps, frame indices, or interval statistics.
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 efficient sentences: the first states the action and secondary check, the second enumerates concrete use cases. Front-loaded and no wasted words, though the sentence structure could be slightly tighter.
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?
Given a single-parameter read-only tool with full schema coverage and no output schema, the description provides sufficient context about what the tool does and why. Missing return-value details, but these are relatively minor for a diagnostic tool.
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 coverage is 100% with a single parameter whose description fully specifies accepted input (local path or http(s) URL). The description adds nothing about parameter semantics, so 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 specific verb (list) and resource (keyframe I-frame times) plus a secondary action (check interval). Distinguishes itself from siblings like video_metadata and detect_shots by focusing specifically on keyframe structure.
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?
Provides clear context for when to use it – diagnosing seek speed, exact-time trimming, and HLS/DASH streaming behavior. Doesn't explicitly name alternatives or exclusions, but the use cases are concrete enough to guide selection.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.