Mac Secrets

mac-secrets

Migrate secrets from plaintext files into macOS Keychain and wire up tooling to read them at runtime. This is a rigid process skill — follow the steps in order.

Why macOS Keychain

macOS Keychain encrypts secrets with the user's login session key. Secrets are only accessible when the session is unlocked and never sit in plaintext on disk. This is the native macOS equivalent of tools like pass, 1password-cli, or vault — no extra dependencies required.

The two key commands:

• Store: security add-generic-password -s '<service>' -a '<account>' -w '<secret>' -U
• Read: security find-generic-password -s '<service>' -a '<account>' -w

The -U flag updates the entry if it already exists (upsert behavior), though on some macOS versions it may fail — see Step 2 for workaround.

How Keychain entries are organized

Each entry has three fields — think of them as a filing system:

-s and -a are just names you choose for finding the secret later. The secret itself goes in -w.

Naming convention

Use claude-code as account for tokens that work across repos (GitLab PAT, GitHub token, OpenAI key). Use the project directory name for tokens scoped to a single project.

Process

Step 1: Identify the secret

Determine (ask the user or infer from context):

Step 2: Store in Keychain

IMPORTANT: Never run the secret as a CLI argument in Claude Code's shell — it would appear in the conversation. Instead, tell the user to run the store command in a separate terminal.

Give the user this command to run in another terminal:

security add-generic-password -s '<service>' -a '<account>' -w

The -w flag without a value prompts interactively for the password — the secret never appears in shell history or on screen.

If -U (upsert) fails with "item already exists", tell the user to delete first:

security delete-generic-password -s '<service>' -a '<account>'
security add-generic-password -s '<service>' -a '<account>' -w

Do NOT use read -s -p — it does not work in zsh (-p means coprocess, not prompt).

Once the user confirms, verify from Claude Code's shell:

security find-generic-password -s '<service>' -a '<account>' -w | head -c 10 && echo "...(ok)"

Step 3: Create a wrapper script (if needed)

Only needed when a tool requires the secret as an environment variable at startup (e.g., MCP servers). Skip this step for secrets read on demand (e.g., curl API calls with $(security ...)).

Template — save as scripts/run-<tool>.sh:

#!/usr/bin/env bash
set -euo pipefail

export <ENV_VAR_NAME>
<ENV_VAR_NAME>="$(security find-generic-password -s '<service>' -a '<account>' -w)"

exec <original-command> "$@"

Key details:

• set -euo pipefail — fail fast on any error
• Declare export and assignment on separate lines — if they're combined (export VAR=$(cmd)), a failing command won't trigger set -e
• exec replaces the shell process with the actual command — no leftover wrapper process
• "$@" passes through any additional arguments

Make the script executable:

chmod +x scripts/run-<tool>.sh

Step 4: Update configuration

Update the relevant configuration files to use the wrapper script instead of the original command.

For MCP servers (.mcp.json):

Before:

{
  "mcpServers": {
    "my-server": {
      "command": "uv",
      "args": ["run", "--directory", ".", "my-server"]
    }
  }
}

After:

{
  "mcpServers": {
    "my-server": {
      "command": "bash",
      "args": ["scripts/run-my-server.sh"]
    }
  }
}

For on-demand API calls (no wrapper needed):

curl -H "PRIVATE-TOKEN: $(security find-generic-password -s 'gitlab-pat' -a 'claude-code' -w)" \
  https://gitlab.example.com/api/v4/...

Step 5: Remove plaintext secrets

Remove the secret from any plaintext file where it previously lived:

• .env files — comment out the line and add a pointer to the Keychain entry:

  # Stored in macOS Keychain (service: <service>, account: <account>)
  # <ENV_VAR_NAME>=
  

• Config files — same pattern: remove the value, leave a comment

Never delete the entire variable reference — the comment serves as documentation for other developers or future-you about where the secret lives.

Step 6: Secure .gitignore

Check that these files are in .gitignore:

• .env (should already be there — verify)
• .mcp.json (contains local paths and tool config)
• Any other file that held the secret

Add missing entries. Don't duplicate existing ones.

Step 7: Verify end-to-end

Run the wrapper script or the tool that consumes the secret and confirm it works. For MCP servers, a quick smoke test:

# Inline Python test — adapt imports to the project
from dotenv import load_dotenv
load_dotenv()
# ... initialize client, make a simple API call, confirm success

Or just launch the tool and check it connects successfully.

Report the final state to the user:

Managing existing secrets

List Keychain entries for a project

security find-generic-password -a '<account>' 2>&1 | grep "svce"

List all Claude Code secrets

security find-generic-password -a 'claude-code' 2>&1 | grep "svce"

Update a secret

Delete and re-add (the -U flag is unreliable on some macOS versions):

security delete-generic-password -s '<service>' -a '<account>'
security add-generic-password -s '<service>' -a '<account>' -w

Delete a secret

security delete-generic-password -s '<service>' -a '<account>'

Multiple secrets in one project

When a project needs several secrets (e.g., an API token and a database password), create one Keychain entry per secret and extend the wrapper script:

#!/usr/bin/env bash
set -euo pipefail

export API_TOKEN DB_PASSWORD

API_TOKEN="$(security find-generic-password -s 'myapp-api-token' -a 'my-project' -w)"
DB_PASSWORD="$(security find-generic-password -s 'myapp-db-password' -a 'my-project' -w)"

exec my-command "$@"

Constraints

• macOS only — this skill uses security(1) which is a macOS-specific tool. For Linux, suggest secret-tool (libsecret) or pass. For cross-platform, suggest 1password-cli or environment-specific vaults.
• Local development only — CI/CD and production environments should use their platform's native secret management (GitHub Secrets, GitLab CI variables, AWS Secrets Manager, etc.).
• One secret per Keychain entry — don't try to store JSON blobs or multiple values in a single entry.