Secrets

How Kortix stores project credentials, and how it controls whether agent code can read each value.

A secret is a per-project credential — an API key, token, or connection string — that a session needs but that must not live in the repository. Kortix stores secrets on the project, never on the account, and encrypts every value with AES-256-GCM using a key derived per project.

Identifier and name

Each secret has two names. The identifier is the handle you use in the CLI and in an agent’s secrets grant. The name is the uppercase environment-variable key in the sandbox, for example STRIPE_API_KEY. In most projects the identifier and the name match. They differ only when a project holds several candidate values for one name — for example, a primary and a backup Google Maps key can both resolve to GOOGLE_MAPS_API_KEY.

Every access rule uses the identifier. None of them uses the name.

Exposure and usage

A secret carries two independent settings. Read them separately; they answer different questions.

Older Kortix documentation presented one list that mixed the two. It is gone. There is no choice between a “network boundary” and an “HTTPS broker”: one mechanism serves every egress-enforced secret on every sandbox provider.

The three exposures

Usages

Most usages are assigned by Kortix, not by you:

• Agent code — implied whenever exposure is not none.
• LLM gateway — assigned when the value is a recognized model-provider key. The gateway authenticates provider requests server-side.
• Connector:<slug> — assigned by the connector binding flow.
• Git — assigned by Kortix for its own Git access. Read-only; you cannot set or clear it.

A secret with exposure none and no usage renders as Disabled: stored, encrypted, and spent by nothing.

Sent secrets and computed secrets

Which exposure a secret can use is a property of the upstream, not of Kortix.

• Sent secrets — the value travels on the wire. API keys, bearer tokens, passwords. This is the vast majority. There is a moment where the value is bytes in an outbound request, so Kortix can put it there itself, outside the sandbox. A sent secret can move to egress-enforced once the secrets_egress flag is on; by default it loads into the sandbox environment.
• Computed secrets — the value is an ingredient in a calculation and never travels. AWS SigV4 signing keys, HMAC webhook-signing secrets, JWT client assertions, SSH private keys. Whoever computes must hold the value. No network boundary helps, because nothing on the wire contains the credential. Computed secrets must stay on environment.

Environment is the default exposure, and the only one that can serve a credential the sandbox has to do math with. Non-HTTPS protocols — a Postgres connection string, SMTP credentials — are in the same position: they must stay on environment.

When you save a value that looks like signing material, such as an AKIA… access-key pair or PEM/SSH material, Kortix defaults it to environment and says why: this key signs requests locally, so egress enforcement cannot apply.

Egress-enforced exposure

The sandbox receives an environment variable whose value is a handle, not the credential. The agent uses that variable exactly as it would use the real key — in a header, a query string, or a body. Authorization: Bearer $VAR, Cookie: …=$VAR, an X-Api-Key header, a query parameter, and a JSON or form body field all work: Kortix finds the handle wherever it appears (raw, URL-encoded, standalone base64, or JSON-escaped) and swaps in the real value. On the way out, Kortix replaces the handle with the real value, but only for requests to hosts you approved.

agent's ordinary HTTP client
  └─▶ in-guest shim (terminates TLS for approved hosts only; holds no secret)
       └─▶ Kortix, server-side
            host allow-list → resolve grant and session allowlist → decrypt
            → substitute handle → call upstream → redact echoes → audit

Facts that follow from that shape:

• The real value is never in the sandbox: not an environment variable, not a file, not an alias.
• A handle sent to a host you did not approve arrives as the literal handle string. The upstream rejects it. It is worth nothing.
• A handle with a bad signature is never honored, and Kortix records it as a forged handle. A valid handle for a secret this session may not spend is recorded as a stolen one.
• The mechanism is identical on every sandbox provider — Daytona, E2B, and Platinum. There is no flag to turn on and no provider to pin.
• Every relayed request writes a per-request audit record.
• Hosts that are not on the list are tunnelled without being read. Pinned-TLS and mTLS clients to those hosts are unaffected.

Hosts match exactly

List every host you call, one exact hostname per line.

api.example.com does not cover uploads.api.example.com. Add the second host to the same secret. Kortix rejects an unenforceable policy with 400 when you save it — it never stores a rule it cannot apply.

Two egress-enforced secrets may share one host. Each handle maps to its own value, so both substitute correctly in the same request.

Verify it with two probes

Run both probes from inside the sandbox, against a host that is on the list. The example uses postman-echo.com, which serves one endpoint of each kind. Add it as an allowed host for the duration of the test.

# 1. Reachability — an endpoint that does NOT echo request headers.
curl -s -o /dev/null -w '%{http_code}\n' https://postman-echo.com/status/200
# expected: 200

# 2. Substitution — an endpoint that DOES echo request headers.
curl -sS -H "authorization: Bearer $STRIPE_API_KEY" https://postman-echo.com/get
# expected: 200, with "Bearer [REDACTED]" in the echoed headers

Read the pair together, probe 1 first: it is the only one that tells you the host is reachable, and probe 2 proves nothing until it passes.

Confirm the real value is nowhere in the guest:

env | grep '^STRIPE_API_KEY='
# expected: the handle, not the credential

The identifier also appears inside KORTIX_SECRET_CAPABILITIES, the value-free catalog that tells the agent which secrets exist, which variable holds each handle, and which hosts each one covers. It never carries a value.

A host on the list presents a certificate Kortix issued for this sandbox, which the sandbox already trusts, rather than the origin’s own:

curl -sv https://postman-echo.com/status/200 2>&1 | grep 'issuer:'
# issuer: CN=Kortix Egress CA (<project prefix>); O=Kortix

What the relay changes

An approved host is reached through Kortix, so it behaves a little differently from a direct call:

• Responses are not streamed. Server-sent events and websockets do not work through an approved host.
• A request body is capped at 1 MiB, a response at 5 MiB, and the whole call at 30 seconds. Kortix follows at most 3 redirects.
• Only a fixed set of response headers comes back — content type and language, caching validators, the rate-limit family, retry-after, x-request-id.
• Only clients that honour https_proxy are intercepted. Kortix sets that variable, and the matching CA trust, in the agent’s environment. A process started with a scrubbed environment calls the host directly, and its request leaves carrying the handle.

For a request Kortix cannot intercept, the agent has an explicit door to the same hosts under the same policy:

kortix secrets call STRIPE_API_KEY https://api.stripe.com/v1/customers

Environment exposure

The sandbox receives the real value as a plain environment variable. Agent code can read it, print it, and forward it anywhere. Kortix cannot redact it, cannot audit its use, and cannot stop it leaving.

Environment is the default exposure. Every new secret uses it unless you move the secret to egress-enforced, which is experimental and needs the secrets_egress flag. A computed credential, and any non-HTTPS protocol, must stay on environment.

Shared and personal scope

A secret is either shared or a personal override:

• Shared — the project-wide value. Every principal with the project.secret.read permission sees every shared secret. Who may read a secret is the permission; which agent receives it is the manifest grant below.
• Personal override — your own value for one name, used instead of the shared row for sessions you start. Today Kortix uses this only for one OAuth login credential.

Kortix never lets an LLM provider key, for example ANTHROPIC_API_KEY, become a personal override. The model gateway always reads the shared row.

Add a secret

kortix secrets set STRIPE_API_KEY=sk_live_...

Grant a secret to an agent

A session receives a secret only when the agent it runs names the identifier in its secrets list. Matching uses the identifier, not the name, and ignores case.

From the dashboard

The Secrets page marks a secret no agent can receive: No agent can receive this secret. Choose an agent there and confirm. Kortix edits kortix.yaml and commits it as chore(agents): grant <IDENTIFIER> to <agent>.

The grant works whether or not the manifest already declares that agent. An agent the manifest does not declare gets a new entry holding this one secrets list. An agent that is already declared keeps every other field — model, tools, connectors — and the identifier joins its existing list. An agent that already admits the identifier needs no commit, and Kortix makes none.

An agent on secrets: all is a special case. all cannot carry an egress-enforced secret, so Kortix writes an explicit list: every identifier the project has today, plus this one. Nothing the agent receives today changes. A secret you add later needs its own grant.

Two cases refuse the grant:

• A project on kortix_version: 1 (kortix.toml) has no agents map to edit. The request fails with 400 and manifest_v1_unsupported. Edit the manifest by hand, or move the project to kortix_version: 2.
• A secret that is Disabled has nothing to deliver. The request fails with 409 and secret_not_grantable. Give it an exposure first.

If the project has no agents: block yet, read The first agents: block changes the whole project before you confirm. That one edit changes secret access for every other agent.

By hand

The same grant, written directly:

kortix_version: 2
agents:
  my-agent:
    secrets: [STRIPE_API_KEY]

The first agents: block changes the whole project

So list every agent that needs secrets, not only the one you are fixing. This is why the dashboard asks you to confirm the first time: after that commit, agents: is the project’s allow-list, and an agent missing from it runs with no project secrets.

Exposing capabilities to third-party users

If you are building something where untrusted third-party users reach a capability — a public chat surface, a shared app, an agent anyone on the internet can prompt — do not hand them secret policies at all. Every user of that surface shares one project agent, one grant, and one host list. Kortix has no way to tell one of your customers from another, so an egress-enforced secret that any user’s prompt can reach is a credential every user can spend, up to the full scope the upstream key carries.

Build the boundary you actually need, on your side:

1. Stand up your own authorization and proxy service. It holds the upstream credential.
2. Point the agent at your service, not at the upstream. Give the agent only a credential for your service — that one can be egress-enforced to your own host.
3. Your service identifies the end user, applies your own authorization rules and per-user quotas, and only then makes the upstream call with the credential it holds.

That service is where per-user rules belong: who may call what, how often, for which records. Kortix secret exposure is one layer below it, and it does not substitute for it.

List your secrets

Run kortix secrets ls to see which secrets a project declares and which ones have a value set.

The list is configuration metadata. It never returns secret values. A scoped agent token sees only identifiers in its agent grant. A session-specific secrets_allowlist controls delivery into that session, but it does not hide configuration metadata that the agent grant permits.

Rotate a secret

kortix secrets set STRIPE_API_KEY=sk_live_new...

Remove a secret

Run kortix secrets unset STRIPE_API_KEY (or unset <identifier>), or delete it from the project’s Secrets page.

Share a value without seeing it

Run kortix secrets request STRIPE_API_KEY to create a link. Anyone with the link can enter the value. You never see it. Links stay valid for 7 days by default; adjust with --expires <minutes> (max 30 days). An expired link shows a clear “expired” page — mint a fresh one with the same command.

End-to-end example

kortix.yaml:

kortix_version: 2
default_agent: my-agent
agents:
  my-agent:
    secrets: [STRIPE_API_KEY]

Secret configuration. The first command stores the value with the default environment exposure. The second moves it to egress-enforced exposure, which is experimental and needs the secrets_egress flag (Settings → Feature flags); it returns 403 feature_disabled while the flag is off.

kortix secrets set STRIPE_API_KEY=sk_live_...
kortix secrets delivery STRIPE_API_KEY egress --allow-host api.stripe.com

The agent then calls Stripe with the variable it was given:

curl -s -o /dev/null -w '%{http_code}\n' \
  -H "authorization: Bearer $STRIPE_API_KEY" \
  https://api.stripe.com/v1/customers
# expected: 200

$STRIPE_API_KEY holds a handle. Stripe receives the real key, because api.stripe.com is on the list. The same request to a host that is not on the list sends the handle, and the upstream rejects it.

The same request from an agent whose secrets list omits STRIPE_API_KEY returns 401. That session starts normally — an ungranted secret is not an error, it is simply never delivered.

CLI commands

The CLI keeps the stored vocabulary: runtime is environment exposure, egress is egress-enforced, denied is disabled. Run kortix secrets --help for every flag.

Setup links default to connector. Use --scope runtime only when the agent’s shell must receive the value. A secret bound to a connector stays server-side.

Names and permissions

Format rules for the two names:

Reading or writing a secret needs the project.secret.read or project.secret.write permission. A project manager holds both. A custom role only adds permissions — Kortix has no deny rule — so no role can withhold either one from a manager. To restrict a manager, remove the manager role.

Delivery to a session is the role verdict of the person who started it, intersected with the launched agent’s manifest grant. Both must allow the secret. See One vocabulary, two bindings.

REST routes

All routes sit under /v1/projects/{projectId}.

POST /secrets rejects names that start with KORTIX_. It returns 409 if the identifier already exists with a different name. It rejects the exact name CODEX_AUTH_JSON with 400 — Kortix manages that secret through ChatGPT subscription onboarding.

Both write routes return a delivery_sync object when the change had to reach running sandboxes. ok: false means the value is saved but at least one live session still uses the previous one; the listed sessions pick it up on restart.

A secret in the list carries delivery_blocked_reason. The value no_agent_grant means no agent can receive this secret. null means it is granted, the exposure needs no grant, or Kortix could not read the manifest.

POST /secrets/{identifier}/grant clears that reason. It returns already_granted: true when the agent’s list already admits the identifier, in which case Kortix commits nothing. It returns adopted_governance: true when the edit added the project’s first agents: block — the change described above. It answers 400 manifest_v1_unsupported for a kortix.toml project and 409 secret_not_grantable for a disabled secret.

Rotation and propagation

A secret write does not wait for a session restart. Kortix pushes the change to every active sandbox in the project:

1. Kortix builds a new environment snapshot, using the running agent’s secrets grant.
2. The sandbox writes the snapshot to the live agent environment. New tool calls pick up the change right away.
3. If the changed secret is an LLM provider credential, Kortix restarts OpenCode.

This push is best-effort. The API call that changes the secret returns before the push finishes. A failed push is only logged, not retried. A sandbox with a failed push keeps the old value until the next successful push, or until the session restarts.

Model credentials

A project on Kortix’s managed model access needs no key of its own. To bring your own, set the provider variables your OpenCode provider config references. A recognized model key is assigned the LLM gateway usage, which spends it server-side; it needs no sandbox presence.

Do not use a generic provider verification result as runtime proof. It cannot prove the selected model, region, entitlement, and API dialect. Send a real prompt through the exact model.