Yichen Jiang
6de470e61b
Review found `127.0.0.2` routed through the proxy. The bypass list carries four literal loopback entries because that is all a consumer reading an environment can match, and `proxyForUrl` matched only those — leaving the rest of `127.0.0.0/8`, `0.0.0.0`, and the IPv4-mapped spellings routed through a proxy that could then reach them. Loopback is now recognised structurally, which a list entry cannot express; the published entries stay for the environment readers. The same review case exposed a wider one. `web_fetch` skips its address checks on a proxied hop, because the proxy resolves the origin — but a literal needs no resolution, so the skip bought nothing and let a proxy on this machine reach every private range those checks refuse, `169.254.169.254` included. A literal the checks would refuse now takes the validated path, where the existing refusal already covers it. Tests that proved a tunnelled hop used a loopback origin, which no policy can route through a proxy any more. They name a host only the proxy can answer for instead — closer to what a proxied request actually looks like. The user guide promised the proxy carried every outbound request including telemetry. It carries neither on an older Node, nor anything a model-authored script sends, so the promise is narrowed and the exceptions listed. A password in a proxy URL reaching every tool DSH runs is documented there too: it is how the variable already behaves, and worth knowing before putting one in.
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Run DSH behind a network proxy
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DSH routes its outbound requests — model calls, web search, page fetches, and MCP servers over HTTP — through the proxy named by the standard proxy environment variables. It reads them at launch; nothing else needs configuring. A few paths stay direct by design or by runtime limit, listed under "What stays direct" below.
Export the variables
export HTTPS_PROXY=http://127.0.0.1:7890
export HTTP_PROXY=http://127.0.0.1:7890
Put both lines in your shell profile so every dsh invocation inherits them. DSH also reads a .env file in the launch directory and in $DSH_HOME, so a proxy that should apply to one project can live there instead; a real environment variable always wins over a file.
A proxy that needs credentials takes them in the URL: http://user:password@proxy.example:8080. DSH never prints the password back — a proxy it reports in a diagnostic shows the username and masks the rest.
Why your browser is proxied but your terminal is not
This is the most common surprise, and it is not specific to DSH. There is no single "system proxy" that all software obeys — there are three unrelated mechanisms:
| Mechanism | Who follows it |
|---|---|
| The operating system's proxy settings | Safari, most native macOS apps, Chrome and Edge |
The HTTP_PROXY / HTTPS_PROXY environment variables |
curl, git, npm, pip, and DSH |
| TUN mode (a virtual network interface) | Everything, transparently |
The "system proxy" switch in a proxy application such as Clash writes only the first one. Browsers pick it up; command-line tools never see it. That is why exporting the variables is a separate step, and why turning on TUN mode makes both work without any variables at all.
DSH does not read the operating system's proxy settings. Export the variables, or use TUN mode.
Choose what stays direct
NO_PROXY lists hosts to reach directly:
export NO_PROXY=internal.example.com,.corp.example.com,registry.local
An entry matches an exact host, a .suffix or *.suffix domain, an optional :port, or * for everything.
CIDR ranges do not work. An operating system bypass list often contains entries like 10.0.0.0/8 or 192.168.0.0/16; copying those into NO_PROXY has no effect. Use host names or domain suffixes instead.
You do not need to list localhost or 127.0.0.1. DSH always bypasses loopback, because its own Web UI and local servers would otherwise route through the proxy and loop.
Limits worth knowing
SOCKS proxies are not supported. A socks5:// value is reported at startup and skipped, and DSH connects directly for the scheme that named it — setting HTTPS_PROXY=socks5://… alongside a usable HTTP_PROXY leaves https: direct rather than borrowing the HTTP proxy. Point the variables at your proxy application's HTTP port instead — most expose both, and the HTTP one is usually a neighbouring port number.
ALL_PROXY alone is enough. DSH falls back to it for both schemes, even though Node and curl differ on this. Setting HTTPS_PROXY explicitly is still clearer.
A TLS-intercepting corporate proxy needs its certificate. If requests fail with a certificate error once the proxy is reachable, point Node at your organisation's CA bundle before launching:
export NODE_EXTRA_CA_CERTS=/path/to/corporate-ca.pem
Node reads that variable only at process start, so export it before running dsh.
Tools DSH runs for you follow the same proxy. Commands in the bash tool, git, gh, and MCP servers started as child processes all inherit these variables. A child that is itself a Node program honors them only on Node 22.21 or later; an older Node connects directly.
A password in the proxy URL reaches those tools too. HTTPS_PROXY=http://alice:s3cret@proxy.example:8080 is a normal environment variable, so every command DSH runs — including the ones the model writes — can read it, and a command that prints its environment puts the password in output that is kept. This is how the variable already behaves for everything else in your shell. If that matters, give the proxy a credential-free entry point, or authenticate it some other way than in the URL.
What stays direct
Not every request DSH makes goes through the proxy:
- Anything on this machine. Loopback is always direct:
localhost, the whole127.0.0.0/8range,::1, and0.0.0.0. A proxy cannot usefully reach a service that only listens locally. - Code the model writes. The workflow and code-runtime workers never receive the proxy settings, so a script the model authors cannot read a proxy URL that may carry a password. Such a script reaches the network only if it configures that itself.
- Telemetry on an older Node. The OTLP exporter uses Node's own HTTP client, which learned to honor these variables in Node 22.21 and 24.5. On 22.19, 22.20, and 24.0–24.4 telemetry connects directly.
web_fetchto a literal private address. A URL naming an address likehttp://10.0.0.5/is refused rather than handed to the proxy, the same refusal it gets with no proxy configured.
Check that it worked
Ask the agent to fetch a page and watch your proxy application's connection log:
dsh --profile headless "fetch https://example.com and tell me the page title"
If the request does not appear there, confirm the variables survive into DSH's own environment:
env | grep -i proxy