This pull request adds opt-in model retry policies across @openai/agents-core, @openai/agents-openai, and @openai/agents-extensions. The core change introduces modelSettings.retry, public retryPolicies helpers, deep merging for nested retry settings, and a shared runner-owned retry path in packages/agents-core/src/model.ts, packages/agents-core/src/runner/modelRetry.ts, packages/agents-core/src/run.ts, packages/agents-core/src/runner/modelSettings.ts, and packages/agents-core/src/agentToolRunConfig.ts.

It also updates provider integrations so OpenAI and AI SDK models expose retry advice instead of making the final retry decision themselves. The OpenAI client calls now force maxRetries: 0 so SDK-level retries cannot bypass the runner policy, while safety vetoes still block retries for aborted requests, streams that already emitted visible output, and websocket requests that may already have been accepted.

This is still opt-in, but if a developers writes some code, this solution could resolve #855. We won't enable such by default, so when we release this enhancement, we'll add guides in documentation.

import { Agent, Runner, retryPolicies, type ModelRetrySettings } from '@openai/agents';

function isTerminatedError(error: unknown): boolean {
  return error instanceof Error && error.message.toLowerCase() === 'terminated';
}

const retry: ModelRetrySettings = {
  maxRetries: 3,
  backoff: {
    initialDelayMs: 250,
    maxDelayMs: 2_000,
    multiplier: 2,
    jitter: true,
  },
  policy: async (context) => {
    if (isTerminatedError(context.error)) {
      return {
        retry: true,
        reason: 'retry on intermittent terminated transport error',
      };
    }

    return retryPolicies.any(
      retryPolicies.providerSuggested(),
      retryPolicies.retryAfter(),
      retryPolicies.networkError(),
      retryPolicies.httpStatus([429, 500, 502, 503, 504]),
    )(context);
  },
};

const runner = new Runner({ modelSettings: { retry } });