Generate and evaluate agent skills based on traces with agents. Create skills with teacher models (expensive/slow) that student models (cheap/fast) can use to perform harder tasks reliably.

Install upskill:

pip install upskill # or just use uv uvx upskill

Create a new skill

upskill generate "write good git commit messages" # or based on previous agent traces upskill generate "document the pattern" --from ./trace.md # Skills are saved to ./skills/{skill-name}/ by default

Generate a skill with a teaching model and evaluate it on a student model.

upskill generate "write good git commit messages" --model sonnet --eval-model haiku

Benchmark a set of models against a skill.

upskill eval ./skills/git-commit-messages/ -m haiku -m sonnet # logs pretty printed to the terminal

View the results later.

upskill runs --skill git-commit-messages

Generate a skill from a task description with automatic evaluation and refinement.

upskill generate TASK [OPTIONS]

Arguments:

• TASK - Description of what the skill should teach

Options:

• -e, --example - Input -> output example (can be repeated)
• --tool - Generate from MCP tool schema (path#tool_name)
• -f, --from PATH - Improve from existing skill dir or agent trace file (auto-detected)
• -m, --model MODEL - Model for generation (e.g., 'sonnet', 'haiku', 'anthropic.claude-sonnet-4-20250514')
• -o, --output PATH - Output directory for skill
• --no-eval - Skip evaluation and refinement
• --eval-model MODEL - Different model to evaluate skill on
• --runs-dir PATH - Directory for run logs (default: ./runs)
• --log-runs / --no-log-runs - Log run data (default: enabled)

Examples:

# Basic usage upskill generate "parse JSON Schema files" # Make and evaluate skills for less powerful models upskill generate "write git commits" --model sonnet --eval-model haiku # Improve an existing skill (auto-detected as directory) upskill generate "add more error handling examples" --from ./skills/api-errors/ # Generate from an agent trace file (auto-detected as file) upskill generate "document the pattern" --from ./trace.json # Skip evaluation during generation (evaluate separately with upskill eval) upskill generate "parse YAML" --no-eval

Output:

Generating skill with sonnet... Generating test cases... Evaluating on sonnet... (attempt 1) 60% -> 100% (+40%) OK git-commit-messages Write clear, conventional commit messages that follow best practices. SKILL.md ~450 tokens baseline ████████████░░░░░░░░ 60% with skill ████████████████████ 100% (+40%) tokens: 1200 → 800 (-33%) Saved to ./skills/git-commit-messages 

Evaluate an existing skill against test cases. Supports single-model evaluation with baseline comparison, or multi-model benchmarking.

upskill eval SKILL_PATH [OPTIONS]

Arguments:

• SKILL_PATH - Path to skill directory containing SKILL.md

Options:

• -t, --tests PATH - Test cases JSON file
• -m, --model MODEL - Model(s) to evaluate against (repeatable for multi-model benchmarking)
• --runs N - Number of runs per model (default: 1)
• --provider [anthropic|openai|generic] - API provider (auto-detected as 'generic' when --base-url is provided)
• --base-url URL - Custom API endpoint for local models
• --no-baseline - Skip baseline comparison
• -v, --verbose - Show per-test results
• --log-runs / --no-log-runs - Log run data (default: enabled)
• --runs-dir PATH - Directory for run logs

Examples:

# Basic evaluation with baseline comparison upskill eval ./skills/my-skill/ # With verbose output upskill eval ./skills/my-skill/ -v # Custom test cases upskill eval ./skills/my-skill/ --tests ./tests.json # Evaluate on specific model upskill eval ./skills/my-skill/ -m haiku # Multi-model benchmarking (compare models) upskill eval ./skills/my-skill/ -m haiku -m sonnet # Multiple runs per model for statistical significance upskill eval ./skills/my-skill/ -m haiku -m sonnet --runs 5 # Evaluate on local model (llama.cpp server) upskill eval ./skills/my-skill/ \ -m "unsloth/GLM-4.7-Flash-GGUF:Q4_0" \ --base-url http://localhost:8080/v1 # Skip baseline (just test with skill) upskill eval ./skills/my-skill/ --no-baseline # Disable run logging upskill eval ./skills/my-skill/ --no-log-runs

Benchmark output:

Evaluating my-skill across 2 model(s) 3 test case(s), 5 run(s) per model haiku Pass rate: 4/5 (80%) Avg assertions: 2.8/3 sonnet Pass rate: 5/5 (100%) Avg assertions: 3.0/3 ┏━━━━━━━━┳━━━━━━━━━━━┳━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━┓ ┃ Model ┃ Pass Rate ┃ Avg Assertions ┃ Avg Tokens ┃ ┡━━━━━━━━╇━━━━━━━━━━━╇━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━┩ │ haiku │ 4/5 │ 2.8/3 │ 1250 │ │ sonnet │ 5/5 │ 3.0/3 │ 1890 │ └────────┴───────────┴────────────────┴────────────┘ 

Test cases JSON format:

[ {"input": "Write a commit for adding login", "expected": {"contains": ["feat", "login"]}}, {"input": "Fix the null pointer bug", "expected": {"contains": ["fix", "bug"]}} ]

List all generated skills in a tree view.

upskill list [OPTIONS]

Options:

• -d, --dir PATH - Skills directory to list
• -v, --verbose - Show skill contents preview

Examples:

# List skills in default directory upskill list # List from custom directory upskill list -d ./my-skills/ # Show preview of skill contents upskill list -v

Output:

./skills ├── git-commit-messages │ ├── Write clear, conventional commit messages... │ └── files │ └── SKILL.md ├── api-error-handling │ ├── Handle API errors gracefully with proper logging... │ └── files │ ├── SKILL.md │ └── references/error-codes.md └── yaml-parsing ├── Parse YAML files safely with schema validation... └── files ├── SKILL.md └── scripts/validate.py 

View run results as a plot, or export to CSV. By default, shows a visual comparison of baseline vs with-skill performance.

upskill runs [OPTIONS]

Options:

• -d, --dir PATH - Runs directory
• -s, --skill TEXT - Filter by skill name(s) (repeatable)
• -m, --model TEXT - Filter by model(s) (repeatable)
• --metric [success|tokens] - Metric to display (default: success)
• --csv PATH - Export to CSV instead of plot

Examples:

# View results plot (default) upskill runs # Filter by skill and models upskill runs -s my-skill -m haiku -m sonnet # Show token usage instead of success rate upskill runs --metric tokens # Export to CSV upskill runs --csv ./results.csv # Custom runs directory upskill runs -d ./my-runs/

Plot output:

skill: git-commit-messages haiku baseline ████████████░░░░░░░░ 60% with skill ████████████████░░░░ 80% (+20%) sonnet baseline ████████████░░░░░░░░ 60% with skill ████████████████████ 100% (+40%) 

Matrix view (multiple skills and models):

┏━━━━━━━━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━┳━━━━━━━━━━━━━━┓ ┃ skill ┃ haiku ┃ sonnet ┃ ┡━━━━━━━━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━╇━━━━━━━━━━━━━━┩ │ git-commit-messages │ 60%→80% │ 60%→100% │ │ api-error-handling │ 40%→70% │ 50%→90% │ │ yaml-parsing │ 70%→90% │ 80%→100% │ └─────────────────────┴──────────────┴──────────────┘ 

Skills are saved in a standard directory format:

./skills/{skill-name}/ ├── SKILL.md # Main skill instructions ├── references/ # Supporting documents (optional) └── scripts/ # Executable scripts (optional) 

Example SKILL.md:

# git-commit-messages Write clear, conventional commit messages that follow best practices. ## Instructions This skill teaches how to write effective git commit messages following the Conventional Commits specification. ## Format Commit messages should follow this structure: <type>(<scope>): <subject> <body> <footer> ## Types - `feat`: New feature - `fix`: Bug fix - `docs`: Documentation changes ... ## Examples ### Simple feature commit feat(auth): add password reset functionality ### Bug fix with explanation fix(api): handle null response from user service The user service can return null when not found. Added proper null checking to prevent crashes. Closes #123

By default, upskill logs all runs to ./runs/. Each run creates:

./runs/ ├── 2025_01_21_15_30/ # Batch folder (timestamp) │ ├── run_1/ │ │ ├── run_metadata.json # Model, task, timing │ │ └── run_result.json # Pass/fail, assertions, tokens │ ├── run_2/ │ │ └── ... │ └── batch_summary.json # Aggregate results └── results.csv # Summary CSV (after `upskill runs`) 

Disable with --no-log-runs.

model: sonnet # Default generation model eval_model: haiku # Default evaluation model (optional) skills_dir: ./skills # Where to save skills runs_dir: ./runs # Where to save run logs max_refine_attempts: 3 # Refinement iterations

Place in your project directory to customize FastAgent settings:

default_model: sonnet logger: progress_display: true show_chat: false streaming: markdown # MCP servers (optional) mcp: servers: fetch: command: "uvx" args: ["mcp-server-fetch"]

# Required for Anthropic models ANTHROPIC_API_KEY=sk-ant-... # Required for OpenAI models OPENAI_API_KEY=sk-... # Optional: custom endpoints ANTHROPIC_BASE_URL=http://localhost:8080 OPENAI_API_BASE=http://localhost:11434/v1 # For local models (generic provider) GENERIC_BASE_URL=http://localhost:8080/v1 GENERIC_API_KEY=local # Optional, defaults to "local"

from upskill import ( generate_skill, generate_tests, evaluate_skill, refine_skill, Config, ) # Load configuration config = Config.load() # Generate a skill skill = await generate_skill( "parse JSON Schema files", model="sonnet", config=config, ) # Generate test cases tests = await generate_tests("parse JSON Schema files") # Evaluate the skill results = await evaluate_skill( skill, tests, model="haiku", config=config, ) print(f"Skill lift: {results.skill_lift:.0%}") print(f"Token savings: {results.token_savings:.0%}") print(f"Is beneficial: {results.is_beneficial}") # Refine based on failures if not results.is_beneficial: from upskill.evaluate import get_failure_descriptions failures = get_failure_descriptions(results) improved_skill = await refine_skill(skill, failures)

upskill uses FastAgent model format:

<provider>.<model>.<reasoning_effort?> 

Examples:

• sonnet - Anthropic Claude Sonnet (alias)
• haiku - Anthropic Claude Haiku (alias)
• opus - Anthropic Claude Opus (alias)
• anthropic.claude-sonnet-4-20250514 - Full model name
• openai.gpt-4.1 - OpenAI GPT-4.1
• openai.o3-mini.low - OpenAI o3-mini with low reasoning effort
• generic.llama3.2:latest - Local model via Ollama
• generic.my-model - Local model via llama.cpp or other OpenAI-compatible server

upskill supports local models through any OpenAI-compatible endpoint (Ollama, llama.cpp, vLLM, etc.).

Quick start with Ollama:

# Start Ollama (default port 11434) ollama serve # Evaluate with a local model upskill eval ./skills/my-skill/ \ --model llama3.2:latest \ --base-url http://localhost:11434/v1

With llama.cpp server:

# Start llama.cpp server ./llama-server -m model.gguf --port 8080 # Evaluate with the local model upskill eval ./skills/my-skill/ \ --model my-model \ --base-url http://localhost:8080/v1

When --base-url is provided, the provider is automatically set to generic unless you specify --provider explicitly.