litellm/docs/my-website/docs/skills.md

/skills - Anthropic Skills API

Feature	Supported
Cost Tracking	✅
Logging	✅
Load Balancing	✅
Supported Providers	anthropic

:::tip

LiteLLM follows the Anthropic Skills API for creating, managing, and using reusable AI capabilities.

:::

LiteLLM Python SDK Usage

Quick Start - Create a Skill

from litellm import create_skill
import zipfile
import os

# Create a SKILL.md file
skill_content = """---
name: test-skill
description: A custom skill for data analysis
---

# Test Skill

This skill helps with data analysis tasks.
"""

# Create skill directory and SKILL.md
os.makedirs("test-skill", exist_ok=True)
with open("test-skill/SKILL.md", "w") as f:
    f.write(skill_content)

# Create a zip file
with zipfile.ZipFile("test-skill.zip", "w") as zipf:
    zipf.write("test-skill/SKILL.md", "test-skill/SKILL.md")

# Create the skill
response = create_skill(
    display_title="My Custom Skill",
    files=[open("test-skill.zip", "rb")],
    custom_llm_provider="anthropic",
    api_key="sk-ant-..."
)

print(f"Skill created: {response.id}")

List Skills

from litellm import list_skills

response = list_skills(
    custom_llm_provider="anthropic",
    api_key="sk-ant-...",
    limit=20
)

for skill in response.data:
    print(f"{skill.display_title}: {skill.id}")

Get Skill Details

from litellm import get_skill

skill = get_skill(
    skill_id="skill_01...",
    custom_llm_provider="anthropic",
    api_key="sk-ant-..."
)

print(f"Skill: {skill.display_title}")
print(f"Description: {skill.description}")

Delete a Skill

from litellm import delete_skill

response = delete_skill(
    skill_id="skill_01...",
    custom_llm_provider="anthropic",
    api_key="sk-ant-..."
)

print(f"Deleted: {response.id}")

Async Usage

from litellm import acreate_skill, alist_skills, aget_skill, adelete_skill
import asyncio

async def manage_skills():
    # Create skill
    with open("test-skill.zip", "rb") as f:
        skill = await acreate_skill(
            display_title="My Async Skill",
            files=[f],
            custom_llm_provider="anthropic",
            api_key="sk-ant-..."
        )
    
    # List skills
    skills = await alist_skills(
        custom_llm_provider="anthropic",
        api_key="sk-ant-..."
    )
    
    # Get skill
    skill_detail = await aget_skill(
        skill_id=skill.id,
        custom_llm_provider="anthropic",
        api_key="sk-ant-..."
    )
    
    # Delete skill (if no versions exist)
    # await adelete_skill(
    #     skill_id=skill.id,
    #     custom_llm_provider="anthropic",
    #     api_key="sk-ant-..."
    # )

asyncio.run(manage_skills())

LiteLLM Proxy Usage

LiteLLM provides Anthropic-compatible /skills endpoints for managing skills.

Authentication

There are two ways to authenticate Skills API requests:

Option 1: Use Default ANTHROPIC_API_KEY

Set the ANTHROPIC_API_KEY environment variable. Requests without a model parameter will use this default key.

# No model_list needed - uses env var
# ANTHROPIC_API_KEY=sk-ant-...

# Request will use ANTHROPIC_API_KEY from environment
curl "http://0.0.0.0:4000/v1/skills?beta=true" \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02"

Option 2: Specify Model for Credential Selection

Define multiple models in your config and use the model parameter to specify which credentials to use.

model_list:
  - model_name: claude-sonnet
    litellm_params:
      model: anthropic/claude-3-5-sonnet-20241022
      api_key: os.environ/ANTHROPIC_API_KEY

Start litellm

litellm --config /path/to/config.yaml

# RUNNING on http://0.0.0.0:4000

Basic Usage

All examples below work with either authentication option (default env key or model-based routing).

Create Skill

You can upload either a ZIP file or directly upload the SKILL.md file:

Option 1: Upload ZIP file

curl "http://0.0.0.0:4000/v1/skills?beta=true" \
  -X POST \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02" \
  -F "display_title=My Skill" \
  -F "files[]=@test-skill.zip"

Option 2: Upload SKILL.md directly

curl "http://0.0.0.0:4000/v1/skills?beta=true" \
  -X POST \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02" \
  -F "display_title=My Skill" \
  -F "files[]=@test-skill/SKILL.md;filename=test-skill/SKILL.md"

List Skills

curl "http://0.0.0.0:4000/v1/skills?beta=true" \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02"

Get Skill

curl "http://0.0.0.0:4000/v1/skills/skill_01abc?beta=true" \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02"

Delete Skill

curl "http://0.0.0.0:4000/v1/skills/skill_01abc?beta=true" \
  -X DELETE \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02"

Model-Based Routing (Multi-Account)

If you have multiple Anthropic accounts, you can use model-based routing to specify which account to use:

model_list:
  - model_name: claude-team-a
    litellm_params:
      model: anthropic/claude-3-5-sonnet-20241022
      api_key: os.environ/ANTHROPIC_API_KEY_TEAM_A
  
  - model_name: claude-team-b
    litellm_params:
      model: anthropic/claude-3-5-sonnet-20241022
      api_key: os.environ/ANTHROPIC_API_KEY_TEAM_B

Then route to specific accounts using the model parameter:

Create Skill with Routing

# Route to Team A - using ZIP file
curl "http://0.0.0.0:4000/v1/skills?beta=true" \
  -X POST \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02" \
  -F "model=claude-team-a" \
  -F "display_title=Team A Skill" \
  -F "files[]=@test-skill.zip"

# Route to Team B - using direct SKILL.md upload
curl "http://0.0.0.0:4000/v1/skills?beta=true" \
  -X POST \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02" \
  -F "model=claude-team-b" \
  -F "display_title=Team B Skill" \
  -F "files[]=@test-skill/SKILL.md;filename=test-skill/SKILL.md"

List Skills with Routing

# List Team A skills
curl "http://0.0.0.0:4000/v1/skills?beta=true&model=claude-team-a" \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02"

# List Team B skills
curl "http://0.0.0.0:4000/v1/skills?beta=true&model=claude-team-b" \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02"

Get Skill with Routing

# Get skill from Team A
curl "http://0.0.0.0:4000/v1/skills/skill_01abc?beta=true&model=claude-team-a" \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02"

# Get skill from Team B
curl "http://0.0.0.0:4000/v1/skills/skill_01xyz?beta=true&model=claude-team-b" \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02"

Delete Skill with Routing

# Delete skill from Team A
curl "http://0.0.0.0:4000/v1/skills/skill_01abc?beta=true&model=claude-team-a" \
  -X DELETE \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02"

# Delete skill from Team B
curl "http://0.0.0.0:4000/v1/skills/skill_01xyz?beta=true&model=claude-team-b" \
  -X DELETE \
  -H "X-Api-Key: sk-1234" \
  -H "anthropic-version: 2023-06-01" \
  -H "anthropic-beta: skills-2025-10-02"

SKILL.md Format

Skills require a SKILL.md file with YAML frontmatter:

---
name: test-skill
description: A brief description of what this skill does
license: MIT
allowed-tools:
  - computer_20250124
  - text_editor_20250124
---

# Test Skill

Detailed instructions for Claude on how to use this skill.

## Usage

Examples and best practices...

YAML Frontmatter Requirements

Field	Required	Description
name	Yes	Skill identifier (lowercase, numbers, hyphens only). Must match the directory name.
description	Yes	Brief description of the skill
license	No	License type (e.g., MIT, Apache-2.0)
allowed-tools	No	List of Claude tools this skill can use
metadata	No	Additional custom metadata

Important: The name field must exactly match your skill directory name. For example, if your directory is test-skill, the frontmatter must have name: test-skill.

File Structure

Option 1: ZIP file structure

Skills must be packaged with a top-level directory matching the skill name:

test-skill.zip
└── test-skill/         # Top-level folder (name must match skill name in SKILL.md)
    └── SKILL.md        # Required skill definition file

All files must be in the same top-level directory, and SKILL.md must be at the root of that directory.

Option 2: Direct SKILL.md upload

When uploading SKILL.md directly (without creating a ZIP), you must include the skill directory path in the filename parameter to preserve the required structure:

# The filename parameter must include the skill directory path
-F "files[]=@test-skill/SKILL.md;filename=test-skill/SKILL.md"

This tells the API that SKILL.md belongs to the test-skill directory.

Important Requirements:

• The folder name (in ZIP or filename path) must exactly match the name field in SKILL.md frontmatter
• SKILL.md must be in the root of the skill directory (not in a subdirectory)
• All additional files must be in the same skill directory

Response Format

Skill Object

{
  "id": "skill_01abc123",
  "type": "skill",
  "name": "my-skill",
  "display_title": "My Custom Skill",
  "description": "A brief description",
  "created_at": "2025-01-15T10:30:00.000Z",
  "updated_at": "2025-01-15T10:30:00.000Z",
  "latest_version_id": "skillver_01xyz789"
}

List Skills Response

{
  "data": [
    {
      "id": "skill_01abc",
      "type": "skill",
      "name": "skill-one",
      "display_title": "Skill One",
      "description": "First skill"
    },
    {
      "id": "skill_02def",
      "type": "skill",
      "name": "skill-two",
      "display_title": "Skill Two",
      "description": "Second skill"
    }
  ],
  "has_more": false,
  "first_id": "skill_01abc",
  "last_id": "skill_02def"
}

Supported Providers

Provider	Link to Usage
Anthropic	Usage