deepseek-ai/deepseek-harness · error · LlmError

UNSUPPORTED_REASONING_EFFORT

UNSUPPORTED_REASONING_EFFORT

Error message

pi-ai provider "${model.provider}" model "${model.id}" does not support reasoning effort "${effort}"

What it means

Error "pi-ai provider "${model.provider}" model "${model.id}" does not support reasoning effort "${effort}"" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/llm/llm-pi-ai/src/adapter.ts:162

function describableReasoningLevel(
  model: Model<Api>,
  effort: ReasoningEffortIdType | ModelThinkingLevel | undefined,
): ModelThinkingLevel | undefined {
  if (effort === undefined) return undefined
  return getSupportedThinkingLevels(model).some(level => level === effort)
    ? effort as ModelThinkingLevel
    : undefined
}

/** Validate an explicit Harness/profile effort without invoking pi-ai's clamp. */
function resolveReasoningLevel(
  model: Model<Api>,
  effort: ReasoningEffortIdType | ModelThinkingLevel | undefined,
): ModelThinkingLevel | undefined {
  if (effort === undefined) return undefined
  const supported = getSupportedThinkingLevels(model)
  if (supported.some(level => level === effort)) return effort as ModelThinkingLevel
  throw new LlmError(
    `pi-ai provider "${model.provider}" model "${model.id}" does not support reasoning effort "${effort}"`,
    'UNSUPPORTED_REASONING_EFFORT',
  )
}

/**
 * Selectable reasoning efforts for one model, or nothing at all.
 *
 * A model that carries no reasoning metadata — every hand-declared one, and
 * every catalog model pi-ai marks as non-reasoning — is reported by pi-ai as
 * supporting the single level `off`. Passing that through would offer a control
 * that cannot do what it says: `off` is translated to *omitting* the reasoning
 * option, which for such a model is byte-for-byte the same request as naming no
 * effort — so a provider whose own default is to think would keep thinking with
 * `off` selected. Omitting `reasoning` entirely is the seam's way of saying the
 * capability is unavailable, which leaves the surface offering only the
 * provider's default.
 * @param model - the resolved model descriptor.

View on GitHub (pinned to b150a551b8)

Solutions

1. Pick a reasoning effort the provider/model supports, or omit it.

When it happens

Trigger: Thrown at packages/llm/llm-pi-ai/src/adapter.ts:162 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of deepseek-ai/deepseek-harness@b150a551b8 (2026-08-24). Data as JSON: /api/errors/3962878770ed8743. Report an issue: GitHub.