Authentication Patterns

What it does

When your agent uses it

• Reviewing service authentication and credential handling
• Tasks that involve Authentication
• Tasks that involve OAuth and OpenID Connect

Example prompts

• “Use the authentication-patterns skill to provide auth patterns for API keys, OAuth, and token management”
• “/authentication-patterns”

Requirements

• Python 3
• A Bash shell
• A credential in API_KEY
• A credential in GEMINI_API_KEY

Workflow steps

3 steps, taken from the step headings in SKILL.md.

1. 1Check Environment
2. 2Verify with Service
3. 3Handle Failures

What it can do on your machine

Read from SKILL.md and the folder at commit 9f3eb00. 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

  Ships script files (Shell), which the agent can run.

  Shell commands in SKILL.md call:

  • gh
  • glab
  • aws
  • pytest

  From the folder's file list and the shell code blocks in SKILL.md.

• Network

  No URLs in SKILL.md. Its commands use gh, glab and aws, which can reach the network depending on how they are called.

  From URLs in SKILL.md, links to its own repository left out.

• Credentials

  Names these keys or tokens, usually read from environment variables:

  • API_KEY
  • GEMINI_API_KEY

  From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.

Context cost

Authentication Patterns loads about 1.2k tokens when it runs. Until then it costs about 43 tokens; SKILL.md has 244 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it

~43

When it runs · the whole SKILL.md, loaded when a task matches

~1.2k

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

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

The full file from athola/claude-night-market at commit 9f3eb00, republished under its MIT licence (© athola). 244 words, ~1,180 tokens.

name

authentication-patterns

description

Provides auth patterns for API keys, OAuth, and token management. Use when implementing or reviewing service authentication and credential handling.

alwaysApply

false

category

infrastructure

tags

authentication, api-keys, oauth, tokens, security

dependencies

error-patterns

provides.infrastructure

authentication, credential-management, auth-verification

provides.patterns

api-key-auth, oauth-flow, token-refresh

usage_patterns

service-authentication, credential-verification, token-management

complexity

beginner

model_hint

fast

estimated_tokens

400

from leyline.auth import verify_auth, AuthMethod

# API Key verification
status = verify_auth(
    service="gemini", method=AuthMethod.API_KEY, env_var="GEMINI_API_KEY"
)

if not status.authenticated:
    print(f"Auth failed: {status.message}")
    print(f"Action: {status.suggested_action}")

def verify_with_smoke_test(service: str) -> bool:
    """Verify auth with simple request."""
    result = execute_simple_request(service, "ping")
    return result.success

def check_credentials(service: str, env_var: str) -> bool:
    value = os.getenv(env_var)
    if not value:
        print(f"Missing {env_var}")
        return False
    return True

def verify_with_service(service: str) -> AuthStatus:
    result = subprocess.run([service, "auth", "status"], capture_output=True)
    return AuthStatus(
        authenticated=(result.returncode == 0), message=result.stdout.decode()
    )

def handle_auth_failure(service: str, method: AuthMethod) -> str:
    actions = {
        AuthMethod.API_KEY: f"Set {service.upper()}_API_KEY environment variable",
        AuthMethod.OAUTH: f"Run '{service} auth login' for browser auth",
        AuthMethod.TOKEN: f"Refresh token with '{service} token refresh'",
    }
    return actions[method]

# In your skill's frontmatter
dependencies: [leyline:authentication-patterns]

# Source the interactive auth script
source plugins/leyline/scripts/interactive_auth.sh

# Ensure authentication before proceeding
ensure_auth github || exit 1
ensure_auth gitlab || exit 1
ensure_auth aws || exit 1

# Continue with authenticated operations
gh pr view 123
glab issue list
aws s3 ls

© athola, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file

Files

SKILL.md and 6 other files in plugins/leyline/skills/authentication-patterns of athola/claude-night-market.

• SKILL.md
• README.md
• examples/workflow-integration.md
• modules/auth-methods.md
• modules/interactive-auth.md
• modules/verification-patterns.md
• tests/test-interactive-auth.sh

Open the folder on GitHubat commit 9f3eb00