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docs(registry/coder/modules/agent-firewall): add Codex MCP TLS workaround note #931

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1b27a42
docs(registry/coder/modules/agent-firewall): add Codex MCP TLS workar…
35C4n0r Jun 22, 2026
ae2e54d
chore(registry/coder/modules/agent-firewall): bump version to 0.0.2
35C4n0r Jun 22, 2026
85a3c78
fix(registry/coder/modules/agent-firewall): revert coder-utils depend…
35C4n0r Jun 22, 2026
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49 changes: 44 additions & 5 deletions registry/coder/modules/agent-firewall/README.md
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Original file line number Diff line number Diff line change
Expand Up @@ -21,7 +21,7 @@ This module:
```tf
module "agent-firewall" {
source = "registry.coder.com/coder/agent-firewall/coder"
version = "0.0.1"

@andrewdennis117 andrewdennis117 Jun 22, 2026

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I see the version has been bumped here to 0.0.2 but in main.tf the version is still 0.0.1 so maybe the version bump script hasn't ran yet. Just wanted to point out the version mismatch

version = "0.0.2"
agent_id = coder_agent.main.id
}
```
Expand All @@ -40,7 +40,7 @@ network-isolated environment.
```tf
module "agent-firewall" {
source = "registry.coder.com/coder/agent-firewall/coder"
version = "0.0.1"
version = "0.0.2"
agent_id = coder_agent.main.id
}

Expand All @@ -65,7 +65,7 @@ resource "coder_script" "claude_with_agent_firewall" {
```tf
module "agent-firewall" {
source = "registry.coder.com/coder/agent-firewall/coder"
version = "0.0.1"
version = "0.0.2"
agent_id = coder_agent.main.id
}

Expand All @@ -82,6 +82,45 @@ resource "coder_app" "claude_with_agent_firewall" {
}
```

### With Codex

Use agent-firewall alongside the `codex` module the same way as other AI modules.

@matifali matifali Jun 22, 2026

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link to module page here on codex


> [!WARNING]
> **MCP subprocesses and TLS verification**
>
> Codex clears the subprocess environment when spawning MCP stdio servers, stripping
> the CA cert and proxy vars that agent-firewall injects into the Codex process.
> This causes MCP subprocesses to fail TLS verification against agent-firewall's
> intercepting proxy. This is a known upstream issue:
> [openai/codex#29124](https://github.com/openai/codex/issues/29124).
>
> **Workaround:** pass the required vars through explicitly via `env_vars` in each
> `[mcp_servers.*]` block in `~/.codex/config.toml`:
>
> ```toml
> [mcp_servers.memory]
> command = "npx"
> args = ["-y", "@modelcontextprotocol/server-memory"]
> env_vars = ["NODE_EXTRA_CA_CERTS", "HTTPS_PROXY"]
> ```
>
> This must be repeated for every MCP server. There is no global default in Codex.
>
> **All vars agent-firewall injects** (from [`landjail/child.go`](https://github.com/coder/boundary/blob/main/landjail/child.go)):
>
> | Variable | Description |
> | ---------------------------- | ---------------------------------------- |
> | `NODE_EXTRA_CA_CERTS` | CA cert for Node.js TLS verification |
> | `SSL_CERT_FILE` | CA cert for OpenSSL/LibreSSL-based tools |
> | `SSL_CERT_DIR` | CA cert directory for OpenSSL |
> | `CURL_CA_BUNDLE` | CA cert for curl |
> | `GIT_SSL_CAINFO` | CA cert for Git |
> | `REQUESTS_CA_BUNDLE` | CA cert for Python requests |
> | `HTTPS_PROXY` / `HTTP_PROXY` | Proxy address for HTTPS/HTTP traffic |
> | `https_proxy` / `http_proxy` | Lowercase aliases for the above |
> | `NO_PROXY` / `no_proxy` | Cleared to prevent bypassing the proxy |

Comment on lines +110 to +123

@matifali matifali Jun 22, 2026

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It is not clear if the user needs to pass all of them or the two shown in the example above.

## Configuration

The module ships with a comprehensive default config based on the
Expand All @@ -104,7 +143,7 @@ Pass the full YAML content directly:
```tf
module "agent-firewall" {
source = "registry.coder.com/coder/agent-firewall/coder"
version = "0.0.1"
version = "0.0.2"
agent_id = coder_agent.main.id

agent_firewall_config = <<-YAML
Expand All @@ -128,7 +167,7 @@ your path. The file must exist on disk before agent-firewall starts.
```tf
module "agent-firewall" {
source = "registry.coder.com/coder/agent-firewall/coder"
version = "0.0.1"
version = "0.0.2"
agent_id = coder_agent.main.id

agent_firewall_config_path = "/workspace/my-agent-firewall-config.yaml"
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