affaan-m/ECC · error · RetrospectiveError

retrospective.mixed_task_families

retrospective.mixed_task_families

Error message

all capsules must have the same task family

What it means

A retrospective can only group capsules from one task family, since the report aggregates runs of comparable tasks. After reading projections, groupCapsules takes the first capsule's task_family and requires every other capsule to match; the first mismatched input (by index) triggers this error. This prevents statistically meaningless comparisons across unrelated task families.

Solutions

  1. Group only capsules that share the same task_family; run a separate retrospective per family
  2. Regenerate the mismatched capsules with the correct task family label
  3. Check each capsule's projection task_family before grouping
  4. If the family was renamed, re-label or re-record old capsules so families align

Example fix

// before
node scripts/eval-harness.js capsule group ./caps-fix-1 ./caps-feature-1  // mixed families
// after
node scripts/eval-harness.js capsule group ./caps-fix-1 ./caps-fix-2      // one family per run
Defensive patterns

Strategy: validation

Validate before calling

// read task_family from each capsule's projection metadata before grouping
const families = new Set(dirs.map(d => readCapsuleFamily(d)));
if (families.size > 1) throw new Error(`mixed task families: ${[...families].join(', ')}`);

Try / catch

try { groupCapsules(dirs); } catch (e) { if (e.code === 'retrospective.mixed_task_families') console.error(`capsule #${e.index} is from a different task family; group per family`); throw e; }

Prevention

When it happens

Trigger: Calling groupCapsules with directories whose capsules were produced for different task families, e.g. mixing 'fix-bug' family capsules with 'add-feature' family capsules; passing capsules from differently named task families after a rename.

Common situations: Aggregating snapshots across repos or task types; a task_family label change in the harness between snapshot generations; copy-pasting a capsule group command that still references directories from a previous, different-family experiment.

Understand the failure class

Background: "is not a compatible type" / "cannot merge" errors: when a value's type doesn't match what the library requires — this error's family across 65 libraries.

Related errors

AI-assisted analysis of affaan-m/ECC@8321021c54 (2026-09-16). Data as JSON: /api/errors/d37b01bdafd0057c. Report an issue: GitHub.

Appendix: source

Thrown at scripts/lib/eval-harness/retrospective.js:74

}

/**
 * Group up to 100 selected snapshots of one task family by harness_version.
 * Duplicate identities count once only if the verified projections match.
 * Different checkpoints of the same identity are ambiguous and refused.
 * Does not read saved projections, copy payloads, write files or invoke tools.
 */
function groupCapsules(dirs) {
  if (!Array.isArray(dirs) || dirs.length < 1 || dirs.length > MAX_INPUTS
      || !Array.from(dirs).every(dir => typeof dir === 'string' && dir.trim() && !dir.includes('\0'))) {
    throw new RetrospectiveError('retrospective.invalid_inputs', `supply 1 to ${MAX_INPUTS} capsule directory paths`);
  }
  const projections = dirs.map(readProjection);
  const family = projections[0].task_family;
  const unique = new Map();
  for (const [index, projection] of projections.entries()) {
    if (projection.task_family !== family) {
      throw new RetrospectiveError('retrospective.mixed_task_families', 'all capsules must have the same task family', index);
    }
    const key = identity(projection);
    const previous = unique.get(key);
    if (previous && previous.projection_hash !== projection.projection_hash) {
      throw new RetrospectiveError('retrospective.conflicting_identity', 'conflicting snapshots share a capsule identity', index);
    }
    unique.set(key, projection);
  }
  const byHarness = new Map();
  for (const projection of unique.values()) {
    const version = projection.harness_version;
    byHarness.set(version, [...(byHarness.get(version) || []), projection]);
  }
  const report = {
    schema: 'capsule-retrospective/v1',
    report_only: true,
    task_family: family,
    input_count: dirs.length,

View on GitHub (pinned to 8321021c54)