Use a Custom Model Provider with DeepSeek Harness
A custom provider must match the protocol expected by its configured route, expose a reachable base URL and advertise a usable model. Validate connectivity and the model list before debugging agents, tools or plugins. This page separates verified behavior from community reports and marks the release-candidate context so you can act without mistaking an observation for a permanent guarantee.
What is verified now
A custom provider must match the protocol expected by its configured route, expose a reachable base URL and advertise a usable model. Validate connectivity and the model list before debugging agents, tools or plugins.
Evidence basis: Official provider guide. The status was checked on 14 August 2026; re-check the linked source after any dsh release.
Safe workflow
Use the smallest reversible workflow first. Do not add community plugins or paste credentials while validating the base behavior.
- Validate the provider base URL and credential source.
- Select an exact model identifier exposed by that route.
- Send a minimal request before enabling tools or plugins.
Verify before moving on
A successful result should be observable: a version string, reachable local URL, valid provider response, loaded configuration, or disappearance of the exact error. If the result differs, stop and capture sanitized evidence rather than stacking unrelated fixes.
- Record the exact dsh, Node or Python version.
- State the operating system and installation method.
- Link the first-party source and include only sanitized logs.
First-party sources
Open the original source before acting on a changed version or unresolved community report.