Vault — Authentication

Secure management and automatic injection of API keys, tokens, and credentials.

Overview

The gateway manages API keys and tokens via a local vault file at ~/.elemm/vault.json. Credentials are automatically injected into outgoing requests based on the target API's hostname.

Vault File Format

json

{
  "api.github.com": {
    "type": "bearer",
    "value": "ghp_your_personal_access_token"
  },
  "api.openweathermap.org": {
    "type": "apiKey",
    "name": "appid",
    "in": "query",
    "value": "your_api_key_here"
  },
  "custom.internal.api": {
    "type": "apiKey",
    "name": "X-Auth-Token",
    "in": "header",
    "value": "secret-123"
  },
  "legacy-service.com": {
    "type": "basic",
    "value": "dXNlcjpwYXNzd29yZA=="
  }
}

Supported Auth Types

Type	Behavior
`apiKey`	Injected as query parameter or header (controlled by the `in` field)
`bearer`	Sets the `Authorization: Bearer` header
`basic`	Sets the `Authorization: Basic` header
(string shorthand)	A plain string value is treated as `apiKey` with `name: "key"` in query

Auth-Aware Validation

The gateway's pre-validation engine is vault-aware: if a required parameter (e.g., appid) is already provided by the vault, it will not be flagged as "missing" during local validation.

Auto-Reload

The vault is re-read from disk on every connect_to_site call. There is no need to restart the gateway after editing vault.json.

Missing Auth Warning

If the target API defines security schemes (in its OpenAPI spec) and no matching vault entry exists, the gateway emits a warning:

[WARNING]
AUTHENTICATION REQUIRED: This site requires apiKey.
REMEDY: Add an entry for 'api.example.com' to your ~/.elemm/vault.json.
INSTRUCTION: Inform the user that an API key is required for this service.

DLP: Automatic Secret Redaction

When prevent_key_leakage: true (default) is set in the Security Policy, all vault API keys are automatically scrubbed from responses before they reach the agent. This prevents credentials from accidentally entering the LLM's context.

Deletion Protection

Before a credential is deleted in the dashboard, the backend checks whether the secret is currently referenced by a registered MCP server. If so, the deletion is refused to prevent runtime failures.