affaan-m/ECC · error · Error

Canonical session snapshot requires ${fieldPath} to be a str

Error message

Canonical session snapshot requires ${fieldPath} to be a string

What it means

Thrown by the ensureStringAllowEmpty helper when a field must be a string but is permitted to be empty, yet the value is not a string at all (number, object, etc.). Currently applied to workers[i].intent.objective, which may be an empty objective string but must still be a string.

Source

Thrown at scripts/lib/session-adapters/canonical-session.js:41

  if (typeof context !== 'string' || context.trim().length === 0) {
    return [];
  }

  return context
    .split('\n')
    .map(line => line.trim())
    .filter(Boolean);
}

function ensureString(value, fieldPath) {
  if (typeof value !== 'string' || value.length === 0) {
    throw new Error(`Canonical session snapshot requires ${fieldPath} to be a non-empty string`);
  }
}

function ensureStringAllowEmpty(value, fieldPath) {
  if (typeof value !== 'string') {
    throw new Error(`Canonical session snapshot requires ${fieldPath} to be a string`);
  }
}

function ensureOptionalString(value, fieldPath) {
  if (value !== null && value !== undefined && typeof value !== 'string') {
    throw new Error(`Canonical session snapshot requires ${fieldPath} to be a string or null`);
  }
}

function ensureBoolean(value, fieldPath) {
  if (typeof value !== 'boolean') {
    throw new Error(`Canonical session snapshot requires ${fieldPath} to be a boolean`);
  }
}

function ensureArrayOfStrings(value, fieldPath) {
  if (!Array.isArray(value) || value.some(item => typeof item !== 'string')) {
    throw new Error(`Canonical session snapshot requires ${fieldPath} to be an array of strings`);

View on GitHub (pinned to 01e15490f0)

Solutions

  1. Coerce the objective to a string when building the worker: String(worker.task.objective || '').
  2. Ensure the source session always provides objective as a string (default to '' if absent).
  3. Validate the worker shape with a fixture before persisting.

Example fix

// before
intent: { objective: worker.task.objective, ... } // task.objective is undefined

// after
intent: { objective: typeof worker.task.objective === 'string' ? worker.task.objective : '', ... }
Defensive patterns

Strategy: validation

Validate before calling

// Coerce objective to a string (empty allowed) before building the worker.
const objective = typeof raw.objective === 'string' ? raw.objective : '';

Type guard

function isStringAllowEmpty(v) { return typeof v === 'string'; }

Prevention

When it happens

Trigger: A worker's intent.objective is set to null, undefined, a number, or an object instead of a string. For example, an adapter assigning objective: worker.task.objective where task.objective is missing and resolves to a non-string.

Common situations: An adapter normalizing a session whose task.objective was never set; a downstream transform that converted the objective to a structured object; a test fixture passing a number for the objective.

Related errors

AI-assisted analysis of affaan-m/ECC@01e15490f0 (2026-08-13). Data as JSON: /api/errors/e5513cca8ebc47df. Report an issue: GitHub.