dsh-proxy-config

One configurable outbound HTTP proxy for DeepSeek Harness, with a live reachability check and an automatic no-proxy fallback while the proxy does not answer — and a switch back to the proxy once it does.

Configuring it is equivalent to writing this into ~/.dsh/.env:

HTTP_PROXY=http://127.0.0.1:11811
HTTPS_PROXY=http://127.0.0.1:11811
ALL_PROXY=http://127.0.0.1:11811
http_proxy=http://127.0.0.1:11811
https_proxy=http://127.0.0.1:11811
all_proxy=http://127.0.0.1:11811
NO_PROXY=localhost,127.0.0.1,::1
no_proxy=localhost,127.0.0.1,::1

The difference is that these values are generated from the plugin's configuration and re-decided on every probe.

Install

Requires DSH 0.2.1-rc.1 or newer (engines.dsh). From the desktop client's plugin directory, or from the command line:

dsh plugin --profile desktop add dsh-proxy-config

From source instead of npm:

dsh plugin --profile desktop add github:dthcle/dsh-proxy-config

The package is a bundle: installing it adds the patch row proxy-config with the schema defaults, so it is active with http://127.0.0.1:11811 as soon as the profile reloads. Nothing is proxied until the endpoint answers — until then the plugin simply reports direct.

Behaviour

1. On mount the plugin probes the configured endpoint (default 127.0.0.1:11811).
2. Endpoint answers — the proxy policy is installed through the harness's own proxy package (@deepseek-ai/dsh-http-proxy, the same module instance the launcher uses): in-process fetch (LLM, web search, HTTP MCP) goes through the proxy, child processes inherit the proxy variables, and the managed block in $DSH_HOME/.env is kept in step so the next launch starts proxied too.
3. Endpoint silent — a real no-proxy fallback: a direct dispatcher is installed, every proxy name is cleared from process.env (which is what a child's environment is built from), and the managed .env block is removed.
4. Every checkIntervalMs (30 s by default) the endpoint is probed again and the proxy is restored once it answers. The decision is hysteretic: unhealthyAfter consecutive failures (default 2) are needed to fall back, healthyAfter successes (default 1) to return, so one timeout never flaps the routing.

Configuration

Every field has a default, so the bare row already targets http://127.0.0.1:11811.

In the desktop client (recommended)

Settings → “HTTP proxy” — a settings page of its own, listed beside General, Models, and Built-in plugins. The top line shows the live state (using the proxy / fallen back to direct / disabled, whether the endpoint answers, the last error, the managed .env state) with a Check now button, followed by four groups of inputs: the endpoint (scheme, host, port, user name, password), routing (enable, bypass list, ALL_PROXY, fallback), probe and fallback, and the Harness-home .env. Save writes the profile's patch layer and applies it immediately — these fields are volatile, so neither a plugin reload nor a client restart is needed. The password is redacted by the Host, so leaving it empty keeps the stored value.

The same form is on sidebar Plugins → dsh-proxy-config → the row proxy-config → Configure.

In the configuration file

Override what you need in the profile's patch layer, for example ~/.dsh/profiles/desktop/cordis.patch.yml:

- id: proxy-config
  name: dsh-proxy-config
  config:
    enabled: true
    host: 127.0.0.1
    port: 11811
    noProxy: localhost,127.0.0.1,::1

Field	Default	Meaning
enabled	true	Apply the proxy. Off removes the managed .env block and applies nothing.
scheme	http	Endpoint scheme; http and https only.
host / port	127.0.0.1 / 11811	The proxy endpoint.
username / password	empty	For a proxy that requires authentication; password carries the secret role.
noProxy	localhost,127.0.0.1,::1	Bypass list; the harness always adds its loopback entries.
includeAllProxy	true	Also publish ALL_PROXY/all_proxy, which non-Node tools read.
fallbackToDirect	true	Connect directly while the proxy does not answer.
probeUrl	empty	An http:// URL fetched through the proxy on every check, to verify forwarding; empty means a connect-only probe.
probeTimeoutMs	1500	Deadline for one probe.
checkIntervalMs	30000	Re-probe interval; 0 probes only at mount, on a config change, and on demand.
unhealthyAfter / healthyAfter	2 / 1	Consecutive failures before falling back / successes before returning.
manageEnvFile / envFile	true / $DSH_HOME/.env	Whether and where the managed .env block lives.

All fields are volatile: an edit applies on the next evaluation without reloading the plugin.

Status tool

proxy_status reports the active mode (proxy, direct, disabled), whether the endpoint answered, the last probe and its error, the proxy variables in effect, the managed .env state, and the time to the next check. recheck: true probes again before reporting.

The managed .env block

The harness accepts proxy names only from the Harness-home .env; a project .env carrying them makes the launcher refuse to start. This plugin owns exactly one marked block there and never touches anything else in the file, and it rewrites the file only when the content actually changes.

# >>> dsh-proxy-config (managed) >>>
HTTP_PROXY=http://127.0.0.1:11811
...
# <<< dsh-proxy-config (managed) <<<

The block is removed while the fallback is active and while the plugin is disabled, so the no-proxy state survives a restart.

Limits

• http:// and https:// proxies only; a SOCKS or PAC value is rejected by the harness package and that scheme stays direct.
• Workflow workers and model-authored scripts do not inherit the proxy, by harness policy.
• Telemetry (OTLP) stays direct by design.
• A mode switch only reaches new children: a persistent shell started while the proxy was active keeps that environment until it restarts, while the harness itself and every newly spawned child follow the current mode immediately.
• Client-side (browser) changes need one window reload in the desktop client; host-side behaviour changes need the bundle switched off and on in the plugin manager.

Development notes

• Installed as a file: directory, this package must declare peerDependencies: { "@deepseek-ai/dsh-http-proxy", "@deepseek-ai/dsh-tools", "@deepseek-ai/schemastery" }. The harness resolver interception supplies its own packages only inside the profile tree or for a linked package that declares them as peers; without that block the plugin fails to load with ERR_MODULE_NOT_FOUND: Cannot find package '@deepseek-ai/schemastery'.
• Host plugin modules are cached by URL: after editing lib/*.js, switch the bundle off and on once in the plugin manager to load the new code. The desktop client picks the browser half (lib/client.js) up on that same switch, so a client restart is normally unnecessary.
• Page text comes from this module's own zh/en dictionaries, chosen by the harness locale (ctx.locale snapshot, falling back to <html lang> / navigator.language). Do not make the text depend on reading back ctx.locale.register: a reload briefly keeps the previous instance alive, the service refuses a duplicate namespace+locale, and a page that relied on that registration degrades into raw keys.
• To verify behaviour, stand in a local forwarding proxy on 11811 and watch whether it receives requests, then stop it and watch the fallback clear the managed .env block within 30–60 seconds.

Verifying

proxy_status(recheck: true)          # agent side
env | grep -i proxy                  # child side (bash)

While the fallback is active, neither should show a proxy variable.