Alter gives AI agents their own keys and an audit trail

A vault for AI agent credentials

Alter, a Y Combinator S25 startup, is building a platform that manages access for AI agents working across multiple users. The company describes itself as offering privileged access management — a system that controls exactly what automated agents can do on behalf of each person who uses them.

In a typical setup today, developers paste API keys into config files, environment variables, and prompts. One "admin" key often powers every agent, giving them broad access they do not need. If something goes wrong, there is no clear record of which agent made a given call or whose account it used.

Alter stores those credentials in a single vault and injects them into requests at runtime, so the keys never appear in code or configuration files ¹.

Per-agent identities and scoped access

The platform gives each agent its own identity with limited permissions, rather than letting every agent borrow the same credential ¹. An incoming request is checked against a set of policies: the system verifies the agent's identity, confirms it has the right scope for the action, checks rate limits, and refreshes tokens when needed .

Calls can be routed through Alter's proxy, which adds its own authorization headers and logs the outcome. An example shown on the company's site tracks a sales agent making a GitHub request, with every step recorded — verification, scope check, token refresh, and the final approval — in a tamper-evident audit log ¹.

For sensitive actions, a human can be placed in the approval chain. The audit trail records not just the action but who approved it, giving teams an answer to questions like "who refunded that charge?" ¹.

Built for multi-user agents and compliance

Alter is designed for developers building AI products that serve many users. It supports 140 integrations, including first-class connections to AWS, LangChain, and MCP (Model Context Protocol), a standard for connecting AI tools to external services ¹.

The platform claims to help products pass security reviews from enterprise customers by offering scoped grants, inspectable policies, and an audit trail that can be streamed to a Security Information and Event Management system ¹. Alter is working toward SOC 2 compliance and publishes a trust center showing its security status .

Use cases covered by the startup include calling APIs on behalf of users, provisioning secrets for backend services, exposing managed credentials to coding agents, and partitioning agent memory by verified identity instead of trusting what a language model claims ¹.

How it works under the hood

Credentials are stored in a dedicated secret store, encrypted at rest, with encryption keys managed outside the application database. If a policy cannot be evaluated, the request is denied by default — a approach called fail-closed authorization ¹. Plaintext credentials are kept out of logs, and proxy-only keys cannot be used to retrieve a stored credential on their own .

Data about keys and references is stored in Postgres, while actual provider tokens live only in the vault ¹.

Key facts

Alter is a Y Combinator S25 startup building privileged access management for AI agents
It gives each agent its own identity and scoped permissions instead of sharing one credential
The platform supports 140 integrations and has first-class connections to AWS, LangChain, and MCP
Alter is working toward SOC 2 compliance and streams audit logs to SIEM systems
A human approval step can be added for sensitive agent actions

Sources

Alter Vault | Privileged Access Management for AI Agents