Distributed Video QA MCP

Cancel a job

video_cancel

Stops a queued or running job while keeping completed stages in the index for reuse.

Instructions

Stop a queued or running job. Stages that already finished stay in the index and are reused.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "job_id": "<job_id>"
    },
    "name": "video_cancel"
  }
}

Input Schema

Name	Required	Description	Default
`job_id`	Yes	Job id to stop.

Output Schema

Name	Required	Description
`kind`	Yes	What the job does.
`next`	No	The call to make to keep waiting, while the job is unfinished.
`error`	No	'code: message — hint' when the job failed.
`stage`	Yes	Current step: queued, download, transcribe, frames, embed or done.
`job_id`	Yes	Pass to video_job to poll, or video_cancel to stop.
`result`	No	When succeeded: the ingest report (video_id, counts, stages, embedding tokens, elapsed seconds) or the download report (path, codecs, size, whether audio was merged).
`source`	Yes	The URL or path being processed.
`status`	Yes	`interrupted` means the server restarted mid-job; ingest again to resume.
`message`	Yes	Latest human-readable progress line.
`progress`	Yes	Overall completion from 0 to 1, weighted by how long each stage usually takes.
`video_id`	No	Known once the source has been resolved; use it with every other tool.
`cancel_requested`	Yes	False when the job had already finished.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.3.0Nov 13, 2026

TDQS

A3.9/5.0

Behavior4/5

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

Annotations only declare the safety profile (not read-only, not destructive, not open-world). The description adds genuinely non-obvious behavior: cancellation is partial, and stages already completed remain in the index and are reused on a later run. It still does not say whether the call is synchronous, whether the job entry is retained, or whether cancel can be undone.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, zero filler, with the action front-loaded and the consequence second. Every clause carries information an agent would otherwise have to guess.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a one-parameter cancel tool with an output schema and annotations covering the safety profile, this is sufficient: the agent knows what gets stopped, what survives, and that the operation is not destructive to completed work.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

There is a single required parameter with 100% schema description coverage ("Job id to stop"), so the schema already carries the semantics. The description adds no format, sourcing, or lookup hint for the job id, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

"Stop a queued or running job" gives a concrete verb plus the resource and even the eligible job states. It is clear enough to separate from deletion-style siblings, though it never names a sibling such as video_delete to make the cancel-vs-delete boundary explicit.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The phrase "queued or running" implies the precondition for calling it, but there is no explicit when-not guidance, no mention of what to do for already-finished jobs, and no named alternative. Usage is inferable but not stated.

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