chroma-core/chroma · error · InvalidConfigurationError

Cannot specify both 'hnsw' and 'spann' configurations during

Error message

Cannot specify both 'hnsw' and 'spann' configurations during update.

What it means

Update-time twin of the creation error: updateCollectionConfigurationToJson throws InvalidConfigurationError when an UpdateCollectionConfiguration contains both hnsw and spann. This code path runs from collection.modify({ configuration }) (Collection.ts) before the updateCollection API call. A collection can only be tuned for the index type it was created with; sending both is rejected client-side.

Source

Thrown at clients/js/packages/chromadb-core/src/CollectionConfiguration.ts:307

    config.sync_threshold = jsonMap.sync_threshold;
  if ("resize_factor" in jsonMap) config.resize_factor = jsonMap.resize_factor;
  return config;
}

export function jsonToUpdateSpannConfiguration(
  jsonMap: Record<string, any>,
): UpdateSpannConfiguration {
  const config: UpdateSpannConfiguration = {};
  if ("search_nprobe" in jsonMap) config.search_nprobe = jsonMap.search_nprobe;
  if ("ef_search" in jsonMap) config.ef_search = jsonMap.ef_search;
  return config;
}

export function updateCollectionConfigurationToJson(
  config: UpdateCollectionConfiguration,
): Record<string, any> {
  if (config.hnsw && config.spann) {
    throw new InvalidConfigurationError(
      "Cannot specify both 'hnsw' and 'spann' configurations during update.",
    );
  }
  let hnswConfig = config.hnsw;
  let spannConfig = config.spann;
  let ef = config.embedding_function;
  let efConfig: Record<string, any> | null | undefined = undefined; // Initialize as undefined

  // Validate HNSW config if present
  if (hnswConfig) {
    if (typeof hnswConfig !== "object") {
      throw new Error(
        "Invalid HNSW config provided in UpdateCollectionConfiguration",
      );
    }
  }

  // Validate SPANN config if present

View on GitHub (pinned to aecdd12c8a)

Solutions

Send only the block matching the collection's actual index type: hnsw for HNSW collections, spann for SPANN collections.
Store which index type the collection was created with (or read it from collection.configuration) and build the update payload from that.
Pre-check the payload: if (cfg.hnsw && cfg.spann) throw before calling modify.

Example fix

// before
await col.modify({
  configuration: { hnsw: { search_ef: 200 }, spann: { search_nprobe: 5 } },
});

// after (collection was created with HNSW)
await col.modify({ configuration: { hnsw: { search_ef: 200 } } });

Defensive patterns

Strategy: validation

Validate before calling

function assertUpdateSingleIndex(cfg: UpdateCollectionConfiguration) {
  if (cfg.hnsw && cfg.spann) {
    throw new Error('Update may target only the index type the collection was created with.');
  }
}
assertUpdateSingleIndex(configuration);
await col.modify({ configuration });

Type guard

function isCleanUpdateConfig(
  cfg: UpdateCollectionConfiguration,
): cfg is UpdateCollectionConfiguration {
  return !(cfg.hnsw && cfg.spann);
}

Try / catch

try {
  await col.modify({ configuration });
} catch (e) {
  if (e instanceof InvalidConfigurationError && e.message.includes('during update')) {
    // keep only the block matching the collection's created index type and retry
  }
  throw e;
}

Prevention

Derive update payloads from the collection's existing configuration instead of reusing create-time or copy-pasted objects.
Track the collection's index type in your own metadata and assert consistency before modify().
Write update helpers that accept exactly one index block.

When it happens

Trigger: collection.modify({ configuration: { hnsw: { search_ef: 200 }, spann: { search_nprobe: 5 } } }); any client.updateCollection-style flow that funnels through loadApiUpdateCollectionConfigurationFromUpdateCollectionConfiguration.

Common situations: Reusing the create-time configuration object (which already has hnsw) and adding spann fields for tuning; copy-pasted update snippets mixing HNSW and SPANN parameters; generic 'update all index knobs' helper that always sets both blocks.

Related errors

AI-assisted analysis of chroma-core/chroma@aecdd12c8a (2026-08-16). Data as JSON: /api/errors/ba9daee044195324. Report an issue: GitHub.