affaan-m/ECC · error

must not contain duplicate values.

Error message

${label} must not contain duplicate values.

What it means

uniqueStrings builds its result with a reduce that rejects any value whose normalized form already appeared earlier in the array, throwing this error. List fields in memory documents must be duplicate-free so tags/links/targets remain unambiguous.

Solutions

1. Deduplicate before calling: Array.from(new Set(values)).
2. Deduplicate on the normalized form (e.g. lowercase/trim each element first) so near-duplicates collapse.
3. Fix the merge logic that appends items already present in the array.
4. Check the error label to identify which list field contains the duplicate.

Example fix

// before
normalizeMemory({ tags: [...oldTags, ...newTags], ... })
// after
normalizeMemory({ tags: [...new Set([...oldTags, ...newTags])], ... })

const dedupe = (arr) => Array.from(new Set(arr.map((s) => String(s).toLowerCase().trim())));

const hasNoDuplicates = (v) => Array.isArray(v) && new Set(v).size === v.length;

try { normalizeMemory(mem); } catch (e) { if (e.message.includes('duplicate')) { mem.tags = dedupe(mem.tags); } else throw e; }

When it happens

Trigger: Passing an array with the same value twice (after per-item validator normalization) to targetHarnesses, normalizeMemory, normalizeScopes, or kinds — e.g. tags: ['tdd', 'TDD'] if the validator lowercases, or an exact duplicate ['tdd', 'tdd'].

Common situations: Merging tag lists from two documents without deduplication; appending to an existing array on each script run; copy-pasting frontmatter where a tag appears in two groups; case differences that normalize to the same value.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• genre numbers must be distinct
• has too many values (maximum ).
• is too long (maximum characters).
• must be a lowercase letters/numbers slug.
• must be a non-empty string.

AI-assisted analysis of affaan-m/ECC@8321021c54 (2026-09-16). Data as JSON: /api/errors/7af48005559c46eb. Report an issue: GitHub.

Appendix: source

Thrown at scripts/lib/memory-vault-format.js:125

function validateMemoryId(value) {
  const normalized = asNonEmptyString(value, 'memory id', 132);
  if (!MEMORY_ID_PATTERN.test(normalized)) {
    throw new Error('memory id must match mem_<lowercase-id> and cannot contain a path.');
  }
  return normalized;
}

function uniqueStrings(values, { label, limit, validator }) {
  if (!Array.isArray(values)) {
    throw new Error(`${label} must be an array.`);
  }
  if (values.length > limit) {
    throw new Error(`${label} has too many values (maximum ${limit}).`);
  }
  return values.reduce((result, value) => {
    const normalized = validator(value);
    if (result.includes(normalized)) {
      throw new Error(`${label} must not contain duplicate values.`);
    }
    return [...result, normalized];
  }, []);
}

function validateTimestamp(value, label) {
  const normalized = asNonEmptyString(value, label, 64);
  const parsed = new Date(normalized);
  if (
    !ISO_TIMESTAMP_PATTERN.test(normalized)
    || Number.isNaN(parsed.getTime())
    || parsed.toISOString() !== normalized
  ) {
    throw new Error(`${label} must be an ISO-8601 timestamp.`);
  }
  return normalized;
}

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