vss-evaluate-caption-accuracy

vss-evaluate-caption-accuracy is a skill for Claude Code, Codex from NVIDIA-AI-Blueprints/video-search-and-summarization. It costs 74 tokens per session (2,186 once invoked), scanned A, original, Apache-2.0.

A procedure for measuring caption accuracy after changing an RT-VLM video-processing setup. It captures baseline and candidate captions, compares them with reference answers using an AI judge, and produces accuracy and processing-time results.

In plain words
What is it for?
Use it to compare two video-captioning configurations against the same videos and review their accuracy and timing.
Why use it?
It shows whether changes to frame selection, video decoding, or model settings improve caption quality or alter processing time.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to compare two video-captioning configurations against the same videos and review their accuracy and timing.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/nvidia-ai-blueprints/video-search-and-summarization/vss-evaluate-caption-accuracy
About the project

NVIDIA AI Blueprint for Video Search and Summarization (VSS) is a reference architecture for applications that use AI to search, analyze, question, and summarize live or recorded video. It is intended for building video analytics agents with vision-language models, language models, retrieval-augmented generation, and NVIDIA NIM microservices. The catalogue entries provide coding-agent rules, skills, commands, agents, instructions, and settings associated with the project.

NVIDIA-AI-Blueprints/video-search-and-summarization · 1,932 stars · on GitHub · build.nvidia.com

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add NVIDIA-AI-Blueprints/video-search-and-summarization --skill vss-evaluate-caption-accuracy
Clone the repo
git clone --depth 1 https://github.com/NVIDIA-AI-Blueprints/video-search-and-summarization

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for vss-evaluate-caption-accuracy

README.md
[![agentmods](https://agentmods.dev/badge/skills/nvidia-ai-blueprints/video-search-and-summarization/vss-evaluate-caption-accuracy/github.svg)](https://agentmods.dev/skills/nvidia-ai-blueprints/video-search-and-summarization/vss-evaluate-caption-accuracy)
Your own site
<a href="https://agentmods.dev/skills/nvidia-ai-blueprints/video-search-and-summarization/vss-evaluate-caption-accuracy"><img src="https://agentmods.dev/badge/skills/nvidia-ai-blueprints/video-search-and-summarization/vss-evaluate-caption-accuracy/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for vss-evaluate-caption-accuracy

Your own site · 80×15
<a href="https://agentmods.dev/skills/nvidia-ai-blueprints/video-search-and-summarization/vss-evaluate-caption-accuracy"><img src="https://agentmods.dev/badge/skills/nvidia-ai-blueprints/video-search-and-summarization/vss-evaluate-caption-accuracy.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 74 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,186 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00074 $0.02186
Opus 5.5 $0.00030 $0.00874
Sonnet 5.5 $0.00015 $0.00437
Haiku 4.5 $0.00007 $0.00219

Measured 17d ago against content hash 1b2ad070d613, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

vss-evaluate-caption-accuracy scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 17d ago.

The scan reads SKILL.md. This mod also ships 5 executable files (scripts/aggregate_table.py, scripts/multi_judge.py, scripts/run_captioning.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/benchmarking/vss-evaluate-caption-accuracy/SKILL.md · 166 lines

How it starts

The opening of the file, as written. The whole thing — 166 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Purpose

Answer one question with evidence: did this RT-VLM change make captions worse?

A configuration change that saves processing time is only useful if caption quality holds. This skill captures captions twice over the same videos — once with the change (HYP) and once without (REF) — scores both against a ground truth using an LLM judge, and reports accuracy delta alongside time saved.

When to Use

  • Before/after changing RT-VLM frame selection, decode, or model settings, to prove there is no caption-quality regression
  • Quantifying accuracy delta and processing-time saved for a candidate config change
  • Verifying a change was behavior-neutral via frame-level provenance, not just matching totals

Not for deploying RT-VLM, general LVS/RTVI benchmarking (see vss-benchmark-video-summarization), or one-off caption spot checks with no paired baseline.

Prerequisites

Everything except the judge runs inside the RT-VLM container. The container needs a GPU, the model on disk, and the nvdsframeselector DeepStream plugin (shipped with DeepStream in the RT-VLM image).

Requirement Notes
Running RT-VLM container Default name rtvi_vlm-$USER. Start it before running any stage
Model weights Set MODEL_PATH in the deployment .env. Runs here used Qwen3-VL-32B-Instruct; any vLLM-compatible VLM works
VLM_MODEL_TO_USE=vllm-compatible In the deployment .env
Source videos A directory of .mp4 files. Point DEDUP_DIR at it
OPENAI_API_KEY In the deployment .env. Only needed for the gt stage (ground truth is gpt-4.1)
claude CLI on the host The judge shells out to it. It is not installed in the container
Deployment inside requires-vss >=3.2.0,<4.0.0, from this skill's front matter. Not enforced automatically — this skill has no preflight.sh, and it drives RT-VLM's OpenAI-compatible HTTP surface directly rather than a VSS deployment origin, so there is no origin here to check. Verify by hand if a deployment's version is in doubt: python3 <repo>/services/agent/scripts/check_vss_version.py <deployment-origin> --skill <this SKILL.md> (0 = compatible, 3 = incompatible, 1 = indeterminate)

Read the full file on GitHub · 166 lines

Files

What ships with it

8 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 17d ago Changed 1b2ad070d613
  2. 18d ago Changed · +8 lines d3b8b0da3b9a
  3. 23d ago Changed · +6 lines 66f14a7d3195
  4. 1mo ago First seen · 152 lines · 74 tokens per session scan A a882c0405b44

Subscribe to this mod's changes

vss-evaluate-caption-accuracy is a skill published in the GitHub repository NVIDIA-AI-Blueprints/video-search-and-summarization (1,932 stars, last pushed today), licensed Apache-2.0. It adds 74 tokens to every session and 2,186 once invoked, about $0.0003 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-15.

Related

Other skills, from other repositories