deepseek-ai/deepseek-harness · error · JsonSchemaError

UNSUPPORTED_SCHEMA

UNSUPPORTED_SCHEMA

Error message

unsupported JSON schema: ${violations.join('; ')}

What it means

Error "unsupported JSON schema: ${violations.join('; ')}" thrown in deepseek-ai/deepseek-harness.

Source

Thrown at packages/core/tools/src/json-schema.ts:388

        break
      }
      /* v8 ignore next -- schemaType was narrowed from the closed SCHEMA_TYPES table above. */
      default: assertNever(schemaType, 'JsonSchemaType')
    }
  }
}

/**
 * Assert that an arbitrary raw schema uses only the enforced subset.
 * Annotation-only schemas are accepted as the standard unconstrained-JSON
 * form; callers that require an object root use {@link assertObjectJsonSchema}.
 * @param schema - untrusted raw JSON Schema.
 * @returns Assertion that the schema belongs to the supported subset.
 */
export function assertSupportedJsonSchema(schema: unknown): asserts schema is JsonSchemaNode {
  const violations: string[] = []
  checkSchemaNode(schema, 'schema', violations, new Set())
  if (violations.length > 0) throw new JsonSchemaError(violations)
}

/**
 * Assert the enforced subset plus the object-root constraint retained by
 * subagent and workflow structured outputs.
 * @param schema - untrusted caller-supplied schema.
 * @returns Assertion that the schema belongs to the supported subset and has an object root.
 */
export function assertObjectJsonSchema(schema: unknown): asserts schema is ObjectJsonSchema {
  const violations: string[] = []
  checkSchemaNode(schema, 'schema', violations, new Set())
  if (violations.length === 0
    && (!isJsonSchemaRecord(schema) || !Object.hasOwn(schema, 'type') || schema.type !== 'object')) {
    violations.push('schema.type must be "object" (structured output is object-rooted)')
  }
  if (violations.length > 0) throw new JsonSchemaError(violations)
}

View on GitHub (pinned to b150a551b8)

When it happens

Trigger: Thrown at packages/core/tools/src/json-schema.ts:388 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/93924108c6a76a53. Report an issue: GitHub.