Keeper Secrets Manager vs Pulumi ESC

Keeper Secrets Manager

Each client device signs requests with its own key, is locked to an IP address by default and can be revoked alone, and secrets decrypt only on the client. The add-on has no public price, no request limits were found in the reviewed documentation, and a person must create the application and device in the vault.

Pulumi ESC

An agent can start without a signup, because the Pulumi CLI creates a free ephemeral account that includes ESC, and the REST API has a public OpenAPI document. Audit logs, custom roles and approvals need the Pro edition at $400 a month, and no API rate limit was found in the reviewed documentation.

Keeper Secrets Manager

1. Ask the vault owner for a new device on an application that holds only the folders the task needs. Use the Base64 configuration, not the first one-time token
2. Run commands under ksm exec so secrets arrive as environment variables and stay out of the model's context
3. Expect HTTP 403 with {"error":"throttled"} under load. The Python SDK retries five times from 11 seconds, so allow for long waits
4. A device is locked to the IP address it first connects from unless it was created with --unlock-ip. Check this before running from a dynamic address
5. Leave --auto-approve off on the MCP server. It removes confirmation for deletes and for unmasking values

Pulumi ESC

1. Use pulumi env, not esc. The standalone CLI stopped at v0.26.0 and gets no security fixes
2. Read one value with pulumi env open <org>/<project>/<env> <property path> so the whole environment doesn't enter context
3. Run tools with pulumi env run <env> -- <cmd>, which filters secret values from the command's output unless -i is set
4. Set PULUMI_ACCESS_TOKEN for the SDKs. From 0.14.0 they no longer read the CLI login on disk
5. Send Authorization: token <token> and Accept: application/vnd.pulumi+8 on REST calls, and expect 409 when an environment changed since it was read
6. Relay the claim link an agent account prints. The account goes read-only after 72 hours and locks after 30 days unclaimed