mastra-ai/mastra · error · Error

Subconscious observation extractor "${name}" shares the Obse

Error message

Subconscious observation extractor "${name}" shares the Observer model and does not accept model or maxSteps.

What it means

Custom (non-built-in) observation extractor entries share the Observer's model by design, so specifying model or maxSteps on them is rejected. This keeps all observation extraction on one model and prevents silent per-extractor model drift.

Source

Thrown at packages/memory/src/processors/observational-memory/subconscious/index.ts:214

      return;
    }
    if (BUILT_IN_OBSERVATION.has(name)) {
      if (name === 'capture') {
        if ('model' in entry || 'maxSteps' in entry) {
          throw new Error('Subconscious capture shares the Observer model and does not accept model or maxSteps.');
        }
        if (
          'schema' in entry &&
          entry.schema &&
          (!('onExtracted' in entry) || typeof entry.onExtracted !== 'function')
        ) {
          throw new Error('A custom capture schema requires an onExtracted hook that handles its output.');
        }
      }
      return;
    }
    if ('model' in entry || 'maxSteps' in entry) {
      throw new Error(
        `Subconscious observation extractor "${name}" shares the Observer model and does not accept model or maxSteps.`,
      );
    }
    if (!('schema' in entry) || !entry.schema || !('onExtracted' in entry) || typeof entry.onExtracted !== 'function') {
      throw new Error(`Custom Subconscious observation agent "${name}" requires schema and onExtracted.`);
    }
  }

  #validateReflectionEntry(entry: SubconsciousReflectionEntry): void {
    const name = entryName(entry);
    if (typeof entry === 'string') {
      if (!BUILT_IN_REFLECTION.has(name)) throw new Error(`Unknown Subconscious reflection agent: ${name}`);
      return;
    }
    if (BUILT_IN_REFLECTION.has(name) && 'agent' in entry && entry.agent) {
      throw new Error(`Built-in Subconscious reflection agent "${name}" cannot be replaced with a custom agent.`);
    }
    if (!BUILT_IN_REFLECTION.has(name) && !entry.instructions?.trim() && !('agent' in entry && entry.agent)) {

View on GitHub (pinned to 75dd419e61)

Solutions

1. Remove model and maxSteps from the custom extractor entry.
2. Set the desired model once on the Observer configuration.
3. If separate models are essential, run multiple Subconscious processors or a custom pipeline outside this option.

Example fix

// before
{ name: 'facts', model: 'gpt-4o-mini', schema: FactsSchema, onExtracted: save }
// after
{ name: 'facts', schema: FactsSchema, onExtracted: save } // model comes from the Observer

const custom = { name: 'facts', model: m, schema: S, onExtracted: f };
if ('model' in custom || 'maxSteps' in custom) throw new Error('custom extractors share the Observer model');

function isCustomExtractorEntry(e: object): boolean {
  return !('model' in e) && !('maxSteps' in e);
}

try {
  sub = new Subconscious({ observation: [entry] });
} catch (e) {
  if (e instanceof Error && e.message.includes('shares the Observer model')) {
    const { model: _m, maxSteps: _s, ...rest } = entry as Record<string, unknown>;
    sub = new Subconscious({ observation: [rest] });
  } else throw e;
}

When it happens

Trigger: new Subconscious({ observation: [{ name: 'my-extractor', model: m, schema: S, onExtracted: f }] }) — any custom entry containing 'model' or 'maxSteps' keys.

Common situations: Copy-pasting agent config into an extractor entry; assuming each extractor can use its own model; migrating from an older API that allowed per-extractor models.

Understand the failure class

Background: "Invalid configuration value" and "Unsupported/Unknown setting value" errors: why libraries reject your config strings, numbers, and types — this error's family across 30 libraries.

Related errors

• observationalMemory.experimental_subconscious must be a Subc
• `retrieval: { vector: true }` requires a vector store. Pass
• `retrieval: { vector: true }` requires an embedder. Pass an
• observation.bufferTokens must be > 0, got ${this.observation
• observation.bufferTokens (${this.observationConfig.bufferTok

AI-assisted analysis of mastra-ai/mastra@75dd419e61 (2026-08-30). Data as JSON: /api/errors/ebc347f2cec4960d. Report an issue: GitHub.