JuliusBrussee/caveman · error · Error

cave_provider_model_identity_mismatch

cave_provider_model_identity_mismatch

Error message

cave_provider_model_identity_mismatch

What it means

Thrown by validateProviderUsage (packages/agent/src/execution-kernel.ts:135): the evidence's provider/model pair does not match the expected pair passed in options.expected. The framework enforces that the model that actually answered is exactly the model that was selected in the plan — no silent substitution by the provider.

Source

Thrown at packages/agent/src/execution-kernel.ts:135

  priced: boolean;
  catalogCostUsd: number;
}

export function validateProviderUsage(
  evidence: ProviderUsageEvidence,
  options: {
    expected?: { provider: string; model: string };
    reportedCostUsd?: number;
    requirePriced?: boolean;
  } = {},
): ValidatedProviderUsage {
  if (typeof evidence.provider !== "string" || evidence.provider.length === 0 ||
      typeof evidence.model !== "string" || evidence.model.length === 0) {
    throw new Error("cave_provider_identity_missing");
  }
  if (options.expected !== undefined &&
      (evidence.provider !== options.expected.provider || evidence.model !== options.expected.model)) {
    throw new Error("cave_provider_model_identity_mismatch");
  }
  const values = [
    evidence.inputTokens,
    evidence.outputTokens,
    evidence.cacheReadTokens,
    evidence.cacheWriteTokens,
    evidence.reasoningTokens,
    evidence.totalTokens,
  ];
  const disjointTotal = evidence.inputTokens + evidence.outputTokens +
    evidence.cacheReadTokens + evidence.cacheWriteTokens;
  if (values.some((value) => !Number.isSafeInteger(value) || value < 0) ||
      evidence.totalTokens <= 0 || evidence.totalTokens !== disjointTotal ||
      evidence.reasoningTokens > evidence.outputTokens) {
    throw new Error("cave_provider_usage_incomplete");
  }
  const priced = catalogCost({
    provider: evidence.provider,

View on GitHub (pinned to 27d5a3981a)

Solutions

1. Compare evidence.model with expected.model strings to see the exact substitution; if the provider legitimately returns a concrete id for your alias, configure the plan with the exact id the provider reports.
2. Regenerate the lock/plan after changing the model so expected identity matches what the provider reports.
3. If a proxy rewrites model names, make it pass the original model string through, or align the configured model with what arrives.

Example fix

// before
validateProviderUsage(evidence, { expected: { provider: "anthropic", model: "claude-sonnet-4-5" } });
// evidence.model === "claude-sonnet-4-20250514"

// after
// configure the plan with the concrete id the provider reports
agent({ model: "anthropic/claude-sonnet-4-20250514", /* ... */ });

function identityMatches(evidence: { provider: string; model: string }, expected: { provider: string; model: string }): boolean {
  return evidence.provider === expected.provider && evidence.model === expected.model;
}
if (expected && !identityMatches(evidence, expected)) {
  console.error(`model substitution: expected ${expected.model}, got ${evidence.model}`);
}

When it happens

Trigger: Calling validateProviderUsage with options.expected set (as locked runs and reserved turns do) while the reported evidence names a different provider or model string (e.g. expected 'anthropic/claude-sonnet-4-5' but the API reported 'claude-sonnet-4-20250514' or a different deployment).

Common situations: Provider aliasing: requesting a model alias and receiving the concrete dated model id back; a gateway/proxy rewriting model names; stale plan/lock expecting an old model id after a provider migration; mismatched casing or whitespace in model strings.

Related errors

• cave_provider_identity_missing
• cave_provider_usage_incomplete
• unsupported provider ${JSON.stringify(value)}
• option not found
• cave_harness_adapter_version_invalid

AI-assisted analysis of JuliusBrussee/caveman@27d5a3981a (2026-08-15). Data as JSON: /api/errors/e98cfd76466a8616. Report an issue: GitHub.