Back Original

Launch HN: Alter (YC S25) – Access control for multi-user agents

Alter Vault | Authorization Enginegnt_7x92k

Incoming Request

A

sales-agent

agent: ai_agent

GET api.github.com/user/repos

Policy Evaluation

✓Identity verified

✓Scope check: repo:read

✓Rate limit: 847 / 1,000

✓Token refreshed (3m ago)

Authorization Result

APPROVED

Injected Headers

Authorization: Bearer ghp_••••••••k4m2

X-Alter-Grant: gnt_7x92k

Audit Log

action: token.proxy

agent: sales-agent

target: github.com

status: 200 OK

latency: 142ms

Give agents their own keys, not yours.

Without Alter

.envOPENAI_API_KEYsystem-prompt.mdSLACK_BOT_TOKENci-config.yamlSTRIPE_SECRET_KEY

Keys scattered everywhere

Pasted into prompts, configs, and .env files across every repo.

admin-key-prodused by: all 14 agents

One key does everything

Every agent borrows the same over-scoped credential.

Who refunded that charge?No results found.

No answers afterward

Nobody can say which agent did what, or on whose behalf.

Building agents

Pass your customers' security review

  • Per-agent identity and scoped grants instead of one shared key
  • Policy and human approval a customer's security team can inspect
  • An audit trail you can hand to a reviewer, streamed to their SIEM
The security review, answered

Securing agents

PAM controls for a new kind of privileged user

  • See every call an agent makes through Alter: which agent, whose access, which policy, who approved
  • Default-deny policy down to the parameter, and approval for risky calls
  • Revoke an agent, key or grant instantly; IdP webhooks cascade offboarding
PAM for AI agents

How it works

Alter authenticates, authorizes, and logs every request

One SDK call handles storage, refresh, policy, and audit for 140 providers. First-class LangChain, MCP, and AWS integrations.

Platform

One platform between your agents and every API

Four features on a single request path.

Use cases

What teams build on Alter

Every card is a working guide with code.

How the platform itself is secured

  • Credentials live in a dedicated secret store, encrypted at rest, with keys managed outside the application database
  • Fail-closed authorization: if a policy cannot be evaluated, the request is denied
  • Zero-trust ownership: a key confers no capability without an explicit record naming it
  • Postgres holds metadata and vault references; provider tokens and credentials live only in the vault
  • Per-key isolation, plaintext credentials never in logs, and proxy-only keys that cannot retrieve a credential at all
Compliance & audit

Controls monitored continuously

SOC 2 in progress

Our trust center publishes the live state of our security program: monitored controls, an independent penetration test within the last 12 months, and security policy documents on request.

Visit the trust center (opens in a new tab)

Put your agents under privileged access control.

Book a 30-minute walkthrough with the founders.