deepseek-ai/deepseek-harness · error · Error

unknown DeepSeek Harness SDK runtime method: ${method}

Error message

unknown DeepSeek Harness SDK runtime method: ${method}

What it means

Error "unknown DeepSeek Harness SDK runtime method: ${method}" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/sdk/server/src/server.ts:199

  }

  /**
   * Dispatch one incoming JSON-RPC request to its typed handler. Throws (→ a
   * JSON-RPC error response) on an unknown method.
   * @param method - the JSON-RPC method name.
   * @param params - the raw params object from the wire.
   * @returns the handler's result, to be serialized as the response.
   */
  async handleRequest(method: string, params: Record<string, unknown> | undefined): Promise<unknown> {
    switch (method) {
      case 'initialize':
        return this.initialize(params as unknown as InitializeParams)
      case 'session/prompt':
        return this.prompt(params as unknown as SessionPromptParams)
      case 'shutdown':
        return this.shutdown()
      default:
        throw new Error(`unknown DeepSeek Harness SDK runtime method: ${method}`)
    }
  }

  private async getOrCreateSession(sessionId: string): Promise<SessionRecord> {
    if (this.shuttingDown) throw new Error('SDK server is shutting down')
    const existing = this.sessions.get(sessionId)
    if (existing) return existing
    const pending = this.sessionCreations.get(sessionId)
    if (pending) return pending
    const creation = this.createSession(sessionId)
    this.sessionCreations.set(sessionId, creation)
    void creation.then(
      () => { this.sessionCreations.delete(sessionId) },
      () => { this.sessionCreations.delete(sessionId) },
    )
    return creation
  }

View on GitHub (pinned to b150a551b8)

Solutions

1. Call only the documented SDK runtime methods; check for an SDK/server version mismatch.

When it happens

Trigger: Thrown at packages/sdk/server/src/server.ts:199 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/95c0ab2a64858ae7. Report an issue: GitHub.