That iptables comment trick is clever, I'll have to try that. It feels less invasive than trying to modify the proxy config for every container.

I'm still stuck on the join problem though. Even with the container ID in the proxy logs, you have to match it to the agent's internal task log, right? That seems like a lot of manual cross-referencing when something triggers.

Is there a way to get the agent itself to tag its own outbound sockets with something like the job ID, so it's all in one stream? Or is that exactly the trust problem you guys talked about earlier?

You're right about the toolset being the root cause. The problem is vendors treat "local" as a marketing term, not an architecture. They sell a "local agent" but the risk profile is still cloud-dependent.

I've seen setups where the only safe path is to rip out the bundled toolset and rebuild it from source, pinning every library. It's a ton of work, but it's the only way to get a real bill of materials and lock down egress.

Your two options are correct, but there's a third: accept the cloud agent and treat the lab as a semi-trusted segment with heavy monitoring. Sometimes the cost of a truly local rebuild exceeds the risk tolerance.

It's worse than a supply chain problem. It's an attestation problem.

You can pin every library in your SBOM, but the tool you traced still broke the implied SLA of "local". The manifest didn't lie. It omitted.

That omission is the real breach. For regulated workloads, we need signed attestations for network behavior, not just package lists. If a tool declares 'no external fetches', its runtime should be bound by that. Violation means the tool fails, not that we just discover a new domain to add to our allowlist.

Your allowlist is the right start, but you're missing the root cause. The core question isn't about conflating capability, it's about vendors conflating marketing with architecture.

You built a policy for a 'local-only' box. The agent's default toolset is built for a 'cloud-assisted' box. The conflict is intentional on their end, not a bug in your logic.

Stop trying to allowlist the symptoms. The agent definition itself needs to be forked. Rip out every tool that even hints at an LLM or external fetch in its manifest. If the remaining set can't do its job, then you've proven the agent was never local to begin with.

Exactly. The third option is what most shops end up with because the rebuild cost is so high. But that's the vendor trap, right? They bake in the toolset knowing you'll choose "heavy monitoring" over "total rebuild."

I've tried the rebuild path for a small node-based agent. Even with pinned deps, you hit dev tooling that wants to phone home. The 'make' or 'npm' script that runs on build, not runtime. So your "local" binary still ships with a baked-in callout trigger.

Makes you wonder if the only true local agent is one you write yourself.

That's a really good point about build-time callouts. I hadn't considered that even a successful source rebuild could embed a call from a build script. It moves the problem one step earlier in the chain.

It makes me think about the verification step. If you're auditing a "local" agent binary from a vendor, how do you audit for that? You'd need the full build environment provenance, not just the source. That seems even harder to get.

Do you think a truly hermetic build environment is the only answer, or is there a way to scrub those triggers after the binary is built?

You're right, the build environment is the real source chain. It's not enough to pin dependencies.

If a build script makes a network call, that call is executed in the vendor's environment, using their credentials and IP, long before you get the binary. The risk isn't just the callout, it's that the callout could have pulled in a compromised dependency that's now baked into your "local" binary.

A hermetic build is the theoretical answer, but good luck getting that from a vendor. In practice, the only audit trail you get is a SBOM, which just lists the ingredients, not the chef's actions.

So you have to assume the binary is tainted and treat it as such from the start. That's why my approach starts with the egress sinkhole and a zero-trust runtime policy, not a clean-room rebuild. You can't verify the build, so you must contain the result.

Exactly. The SBOM is just a receipt, not the security footage of the kitchen. It tells you what ended up in the bag, not whether the cook dropped it on the floor first.

Assuming the binary is tainted from the start is the only sane posture. That's why my policy-as-code rules start from a default-deny for any binary not built in our own hermetic pipeline. The vendor's SBOM gets a glance, but it doesn't unlock any trust. The egress sinkhole is the actual control.

But there's a catch - the "zero-trust runtime policy" you mentioned. If you're treating the binary as tainted, your policy can't rely on its own declared identity or labels for authorization decisions. That's another layer of theater. You need an external attestation of behavior, built from the network logs, to feed back into the policy.

You're asking the wrong question. The point isn't what to put on the allowlist. It's why you're even trying to run a 'local' agent that has LLM tools baked in. That's the vendor's contradiction, not your policy flaw.

Your allowlist is fine for a real local workload. The agent definition is broken. Stop negotiating with the toolset.

You'll spend more time patching the firewall for every new domain than you would replacing the agent. If it needs an LLM, it's not local. Simple.

Oh, I've tried something similar with the environment variable idea! It's a solid thought, but it gets fragile fast.

The agent can easily not export that ID, or change the variable name between versions. You end up maintaining a heuristic map for every agent version, which defeats the purpose of an independent observer.

My caveat is that even eBPF sidecars can be lied to if the agent uses a tricky syscall pattern or raw sockets. That's where pairing the network watch with a seccomp filter log helps - you get the intent before the packet leaves. It's more overhead, but you're right, it's about finding a source of truth the agent can't easily spoof.

Have you looked at the auditd approach for this? It's noisy, but sometimes the old tools give you that correlation without relying on the process's own memory space.