deepseek-ai/deepseek-harness · error

acp: connection closed with an error: ${String(error)}

Error message

acp: connection closed with an error: ${String(error)}

What it means

Error "acp: connection closed with an error: ${String(error)}" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/acp/acp/src/index.ts:515

      }
      if (failures.length > 0) {
        // The production consumer logs this AggregateError through `String`,
        // which renders only its message. Embed every per-session diagnostic,
        // including nested causes and aggregate members, in that message.
        const detail = failures.map(failure => errorChain(failure)).join('; ')
        throw new AggregateError(
          failures,
          `ACP agent teardown failed for ${failures.length} session(s): ${detail}`,
        )
      }
    })()
    return quiescing
  }

  /* v8 ignore start -- production transport rejection and teardown failure. */
  void conn.closed
    .catch((error: unknown) => {
      logger.warn(`acp: connection closed with an error: ${String(error)}`)
    })
    .then(quiesce)
    .catch((error: unknown) => {
      logger.warn(`acp: connection-close teardown failed: ${String(error)}`)
    })
  /* v8 ignore stop */

  ctx.effect(() => quiesce, 'acp.connection')
}

/**
 * Build per-agent options from plugin config without assigning absent optional fields.
 * @param config - ACP provider/model configuration.
 * @returns the configured fields only.
 */
function agentOptions(config: AcpConfig): { provider?: string; model?: string } {
  return {
    ...config.provider !== undefined ? { provider: config.provider } : {},

View on GitHub (pinned to b150a551b8)

Solutions

1. Inspect the connection error in the log and re-establish the ACP connection.

When it happens

Trigger: Thrown at packages/acp/acp/src/index.ts:515 when the library encounters an invalid state.

Common situations: See trigger scenarios.

Understand the failure class

• Connection failures: ECONNREFUSED, ECONNRESET, and friends — why connections get refused, reset, or dropped.

AI-assisted analysis of deepseek-ai/deepseek-harness@b150a551b8 (2026-08-24). Data as JSON: /api/errors/ff593e274c9b665b. Report an issue: GitHub.