[nlundee]

What and why

Proposes ADR 0043: the platform never runs code that a model, a user or a tenant writes. When a service needs code to run, it calls an agent in agentctl, which already gives each agent an isolated computer with mediated network and no real secrets inside.

• The platform does not run code. No interpreter, shell, child_process, vm or worker_threads in the API, the worker or the packages. A new dependency rule, no-code-execution-in-the-platform in .dependency-cruiser.cjs, enforces it outside test files. Nothing imports them today.
• A service that needs code calls an agent in agentctl through the routes ADR 0028 already has: as a registered tool (MCP, OpenAPI or A2A, granted in spec.tools) or as a remote-agent. Everything ADR 0015 and 0028 keep at the boundary applies unchanged: the grant, the egress guard, secrets bound to the agent's host, untrusted results, timeouts, cost and audit.
• An agent in agentctl uses the platform like any client: the open API, MCP or /v1 with a tenant key, which can only ask questions. Changes to services go through proposals that a person approves (ADR 0020, 0026).
• Turned down: a sandbox inside the platform (as in ADR 0028), running every platform session inside agentctl (the platform's tool calls are HTTP through the egress guard, so a VM per session would add cost without isolating more), and moving datasets, rights or evaluation into agentctl.
• Not built: no agent in agentctl is reachable as an MCP, A2A or remote-agent/v1 endpoint yet, and agentd would need to run on a host a tenant can register.

The number is 0043 because 0041 and 0042 are taken by #179 and #125.

How it was tested

• npm run boundaries passes with the new rule (1,647 modules). With a temporary import { execSync } from 'node:child_process' in packages/kernel/src, it fails with no-code-execution-in-the-platform.

• npm run check: 460 test files pass and 1 is skipped (4,906 tests pass, 12 skipped).

• npx prettier --check docs/adr .dependency-cruiser.cjs.

• npm run check passes

Checklist

• Every new rule has a test whose name states it
• User-facing text is in the i18n catalogues, in bokmål and English, with no em-dashes
• Vendor SDKs stay in packages/providers-*
• ADRs, docs and docs/architecture/modules are updated if a contract, boundary or module changed
• No secrets, personal data or local paths