Infisical vs Pulumi ESC

Infisical

Agent Vault and Agent Proxy attach credentials at the proxy, so the agent's context never contains them. Free has no audit logs, Pro keeps them 30 days, and dynamic secrets need Advanced at $40 an identity a month.

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.

Infisical

1. Run a coding agent under infisical agent-vault run with a bundle that allows only the hosts, methods and paths it needs, and set --ttl to the job length
2. Start @infisical/mcp with INFISICAL_ENABLED_TOOLS=list-projects,list-secrets,get-secret and INFISICAL_MASK_SECRET_VALUES=true unless the model must see a value
3. Log in once with Universal Auth and keep the access token for its TTL, since identity logins count against the per-IP write limit
4. Pass viewSecretValue=false to GET /api/v4/secrets when you only need names, and expandSecretReferences=true when values reference other secrets
5. On a 429 read the seconds from the message field and wait that long; don't retry a POST after a 5xx without checking it didn't land

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