Prompt Lab
Mathews-Tom/armory
LLM prompt engineering: analyzes failure modes, generates variants (direct, few-shot, CoT), designs rubrics, produces test suites.
Universal quality bar and final audit rubric for any agent system prompt.
Install Agent Prompt Quality Bar
$ npx skills add mastra-ai/mastra --skill agent-prompt-quality-bar -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install mastra-ai/mastra agent-prompt-quality-bar --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/mastra-ai/mastra.git skills-src && mkdir -p .claude/skills && cp -r skills-src/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar .claude/skills/agent-prompt-quality-bar && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "agent-prompt-quality-bar" agent skill from https://github.com/mastra-ai/mastra/tree/main/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar into .claude/skills/agent-prompt-quality-bar/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "agent-prompt-quality-bar", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/mastra-ai/mastra/tree/main/packages/editor/src/ee/workspace/skills/agent-prompt-quality-barType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add mastra-ai/mastra --skill agent-prompt-quality-bar -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install mastra-ai/mastra agent-prompt-quality-bar --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mastra-ai/mastra.git skills-src && mkdir -p .agents/skills && cp -r skills-src/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar .agents/skills/agent-prompt-quality-bar && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "agent-prompt-quality-bar" agent skill from https://github.com/mastra-ai/mastra/tree/main/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar into .agents/skills/agent-prompt-quality-bar/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "agent-prompt-quality-bar", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add mastra-ai/mastra --skill agent-prompt-quality-bar -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install mastra-ai/mastra agent-prompt-quality-bar --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mastra-ai/mastra.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar .cursor/skills/agent-prompt-quality-bar && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "agent-prompt-quality-bar" agent skill from https://github.com/mastra-ai/mastra/tree/main/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar into .cursor/skills/agent-prompt-quality-bar/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "agent-prompt-quality-bar", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/mastra-ai/mastra.git --path packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add mastra-ai/mastra --skill agent-prompt-quality-bar -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install mastra-ai/mastra agent-prompt-quality-bar --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mastra-ai/mastra.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar .gemini/skills/agent-prompt-quality-bar && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "agent-prompt-quality-bar" agent skill from https://github.com/mastra-ai/mastra/tree/main/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar into .gemini/skills/agent-prompt-quality-bar/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "agent-prompt-quality-bar", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install mastra-ai/mastra agent-prompt-quality-barInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add mastra-ai/mastra --skill agent-prompt-quality-bar -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/mastra-ai/mastra.git skills-src && mkdir -p .github/skills && cp -r skills-src/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar .github/skills/agent-prompt-quality-bar && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "agent-prompt-quality-bar" agent skill from https://github.com/mastra-ai/mastra/tree/main/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar into .github/skills/agent-prompt-quality-bar/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "agent-prompt-quality-bar", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add mastra-ai/mastra --skill agent-prompt-quality-bar -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install mastra-ai/mastra agent-prompt-quality-bar --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/mastra-ai/mastra.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar .opencode/skills/agent-prompt-quality-bar && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "agent-prompt-quality-bar" agent skill from https://github.com/mastra-ai/mastra/tree/main/packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar into .opencode/skills/agent-prompt-quality-bar/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "agent-prompt-quality-bar", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
agent-prompt-quality-bar- GitHub stars
- 29k
- Token cost
- ~2k tokens
- SKILL.md length
- 1,047 words
- Files
- 1
- Skills in repo
- 44
- Repo updated
- First seen
- Licence
- Custom licence
At a glance
Universal quality bar and final audit rubric for any agent system prompt.
- Works in 9 steps: Role and outcome → Trigger and input → Decision rules → …
- Tasks that involve Prompt engineering
- SKILL.md covers Required run contract, Non-negotiable sections, Mandatory final audit rubric and Universal anti-patterns to…, plus 2 more sections
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Agent Prompt Quality Bar is an agent skill from mastra-ai/mastra. Universal quality bar and final audit rubric for any agent system prompt. Activate this whenever you are unsure which archetype skill applies, or as a final review pass before writing the system prompt. It defines the required run contract, completion criteria, fallback paths, response format, and anti-patterns every produced agent prompt must satisfy.
Its SKILL.md is about 2k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
It sits in AI & LLM Engineering, covering Prompt engineering, Structured output and tool calling and Quizzes and assessments. The repository describes itself as: Mastra is the modern TypeScript framework for AI-powered applications and agents.
When your agent uses it
- Tasks that involve Prompt engineering
- Tasks that involve Structured output and tool calling
- Tasks that involve Quizzes and assessments
Example prompts
- “/agent-prompt-quality-bar”
Workflow steps
9 steps, taken from the step headings in SKILL.md.
- Role and outcome
- Trigger and input
- Decision rules
- Capability awareness
- Missing-capability fallback
- Communication style and final response format
- Refusals and escalations
- Completion criteria
- Worked example
What it can do on your machine
Read from SKILL.md and the folder at commit b98829a. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md.
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Agent Prompt Quality Bar loads about 2k tokens when it runs. Until then it costs about 95 tokens; SKILL.md has 1,047 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
Its licence (Custom licence) doesn't allow us to republish the file, so here is its outline and opening line. It has 1,047 words (~1,970 tokens).
“This is the builder's compile check. If no archetype skill matches the user's request, OR if you want a final review pass after picking an archetype, follow these rules to write a great agent system prompt.”
- name
- agent-prompt-quality-bar
Files
Just SKILL.md in packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar of mastra-ai/mastra.
Open the folder on GitHubat commit b98829a
Compare with similar skills
Agent Prompt Quality Bar next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Agent Prompt Quality Bar this skillmastra-ai/mastra | 29k | — | ~2k | Automated safety check: Pass | Custom licence | |
| Prompt LabMathews-Tom/armory | 329 | — | ~2.1k | Automated safety check: Pass | MIT | |
| Generate Verifiers Envadithya-s-k/FineEnvs | 461 | 1 repos | ~2.3k | Automated safety check: Pass | Apache-2.0 | |
| Prompt Engineering Patternswshobson/agents | 40k | — | ~1.3k | Automated safety check: Pass | MIT | |
| Kayba Stage 2 Domain Contextkayba-ai/agentic-context-engine | 2.6k | — | ~1.9k | Automated safety check: Pass | Apache-2.0 | |
| Lintlanghermes-labs-ai/lintlang | 140 | — | ~719 | Automated safety check: Pass | Apache-2.0 |
Similar skills
Generate Verifiers Env
adithya-s-k/FineEnvs
Builds a Verifiers (PrimeIntellect) variant of an RL environment.
Prompt Engineering Patterns
wshobson/agents
Reference for designing and tuning production LLM prompts: few-shot examples, chain-of-thought, structured outputs, templates and system prompts.
Kayba Stage 2 Domain Context
kayba-ai/agentic-context-engine
Gather domain context about the repository and agent — system prompt, tool definitions, domain docs, and behavior patterns from traces.
Lintlang
hermes-labs-ai/lintlang
A skill your agent uses when writing or reviewing AI agent configs, system prompts, or tool definitions (JSON/YAML/Python) and you need to catch ambiguous tool descriptions, missing stop conditions…
Lintlang Audit
hermes-labs-ai/lintlang
Audit a named AI agent config, system prompt, tool definition, or instruction file (YAML, JSON, Markdown, text, or Python) with the released LintLang CLI in GitHub Copilot CLI.
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Related
Categories
Questions about Agent Prompt Quality Bar
What does Agent Prompt Quality Bar do?
Universal quality bar and final audit rubric for any agent system prompt. Agent Prompt Quality Bar is an agent skill from mastra-ai/mastra. Universal quality bar and final audit rubric for any agent system prompt.
When should I use Agent Prompt Quality Bar?
Agent Prompt Quality Bar fits situations like: tasks that involve Prompt engineering; tasks that involve Structured output and tool calling; tasks that involve Quizzes and assessments.
How do I install Agent Prompt Quality Bar in Claude Code?
Run `npx skills add mastra-ai/mastra --skill agent-prompt-quality-bar -a claude-code`. Or copy the skill folder (packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar in mastra-ai/mastra) into .claude/skills/agent-prompt-quality-bar in your project. Claude Code loads it when a task matches its description.
How do I install Agent Prompt Quality Bar in Codex?
Run `npx skills add mastra-ai/mastra --skill agent-prompt-quality-bar -a codex`. Or copy the skill folder (packages/editor/src/ee/workspace/skills/agent-prompt-quality-bar in mastra-ai/mastra) into .agents/skills/agent-prompt-quality-bar in your project. Codex loads it when a task matches its description.
Can I use Agent Prompt Quality Bar in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add mastra-ai/mastra --skill agent-prompt-quality-bar -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/agent-prompt-quality-bar, .gemini/skills/agent-prompt-quality-bar, .github/skills/agent-prompt-quality-bar and .opencode/skills/agent-prompt-quality-bar in your project.
What does Agent Prompt Quality Bar need to run?
SKILL.md names no scripts, command-line tools or credentials: Agent Prompt Quality Bar is instructions for the agent only.
Does Agent Prompt Quality Bar access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Agent Prompt Quality Bar safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Agent Prompt Quality Bar use?
Agent Prompt Quality Bar has a licence file (the repository's licence) that doesn't match a standard licence. Read it on GitHub before reusing the skill.
How many tokens does Agent Prompt Quality Bar use?
About 2k tokens (SKILL.md is roughly 7.9k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Agent Prompt Quality Bar?
Skills that share tags, products or a category with Agent Prompt Quality Bar: Prompt Lab (Mathews-Tom/armory, 329 stars), Generate Verifiers Env (adithya-s-k/FineEnvs, 461 stars), Prompt Engineering Patterns (wshobson/agents, 40k stars) and Kayba Stage 2 Domain Context (kayba-ai/agentic-context-engine, 2.6k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Agent Prompt Quality Bar?
mastra-ai (a GitHub organization) maintains it in mastra-ai/mastra, which has 28,698 GitHub stars. The repository holds 44 skills in this directory. The repository was last updated on October 11, 2026.
Source: mastra-ai/mastra on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.