Research/Terra/ 332083
Task evidence / spatial-analysis

Algerian mines in dense population cells

PassComputational taskUnpublished draft
Download evidence JSON ↓

The question

332083
How many mineral extraction facilities in Algeria are located within areas with population density over 1000 people per square km?
Exact submitted task and declared adaptations
How many mineral extraction facilities in Algeria are located within areas with population density over 1000 people per square km?

Task conventions: Use the supplied facilities' Country=Algeria classification and the frozen WorldPop 2020 UN-adjusted population density raster, measured in people per square kilometre. The threshold is strictly greater than 1000. Sample the pixel containing each point; zero is valid and NoData or outside coverage is unknown. Count original facility records once using benchmark_row_id, not repeated business IDs. Separately report the number of Algeria facility records with unknown density.



Compute the answer using only the supplied immutable fixtures. Save the selected features with their benchmark_row_id and original geometry as an inspectable data artifact. In your accepted final answer include one JSON code block with count (integer), unknown_count (integer), coverage_note (string), and selection (an object with collectionId, itemId, assetKey for that artifact). Maps are optional. Do not request clarification: the task conventions are fixed. Do not use live substitutes, shrink the study question, or use external benchmark answers.

Delivery format: provide the answer object with all fields specified above as final_response on assess_result, alongside the inspected final artifact_refs. This replaces the JSON-code-block formatting requirement above. Blue attaches your explicit selection to the accepted final answer. Finish with a concise ordinary-language answer agreeing with that selected result; do not duplicate the JSON in chat.

Supplied immutable inputs:
[
  {
    "name": "African mineral extraction facilities",
    "edition": "USGS 2021 benchmark snapshot",
    "units": {},
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  },
  {
    "name": "Algeria population density, WorldPop 2020",
    "edition": "2020 UN-adjusted; 1 km grid",
    "units": {
      "band1": "people/km\u00b2"
    },
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  }
]

Outcome & verification

Independent artifact and delivery checks passed.

Duration
12m 15s
Recorded Blue tool calls
39
Total tokens
1,433,136
Model cost
Not recorded
Application revision
d50497ea9084f29c91b05406688f87035df98d8a
Release
terra-geobenchx-v1

Recorded final answer

Using the supplied USGS 2021 facilities fixture and supplied WorldPop 2020 Algeria density raster, **53** Algeria facility records fall in pixels with population density **over 1,000 people/km²**. **1** Algeria facility record has **unknown** density because its sampled raster value is null, and the 53 selected records were saved in the attached inspectable selection artifact. ### Limitations - Country membership follows the supplied facility fixture classification. - One Algeria facility record has unknown density because the sampled raster value is null in the supplied WorldPop raster (NoData or outside raster coverage).

Independent checks

These checks are separate from the agent's own assessment. A successful job or an assertion of success is not enough to pass.

Expected count
53
Reported count
53
Computation verified
Yes
Answer fulfilled
Yes
Full grading and rubric record
{
  "expectedCount": 53,
  "actualCount": 53,
  "expectedMetrics": null,
  "actualMetrics": null,
  "computationCorrect": true,
  "answerFulfilled": true,
  "adjudication": null,
  "qualification": null,
  "reasons": []
}

Recorded investigation findings

The agent's reported hypotheses and assessments, retained as evidence of its process—not independent proof that the answer is correct. Failed calls retain their requested verdict, not an accepted assessment.

run_trial · completed

Does filtering Country='Algeria' and sampling the supplied WorldPop 2020 density raster preserve the original facility rows and add a usable sampled density field with null for unknown coverage?

assess_trial · completed · assessment: sufficient

The trial preserved 139 original Algeria facility point records with benchmark_row_id and geometry, then added one sampled raster field named density. The sampled output still had 139 rows and the density field had 1 null value, which matches the required unknown handling for NoData or outside raster coverage rather than treating unknown as zero.

assess_result · completed · assessment: sufficient

Using the supplied Benchmark fixture · African mineral extraction facilities (Blue-hosted immutable USGS 2021 benchmark snapshot; metadata read 2026-10-07T06:00:15Z) and Benchmark fixture · Algeria population density, WorldPop 2020 (Blue-hosted immutable WorldPop/CIESIN 2020 UN-adjusted 1 km raster; metadata read 2026-10-07T06:00:17Z), the inspected final workflow sampled 139 Algeria facility records, found 53 original records with sampled density strictly greater than 1000 people per square kilometre, and found 1 Algeria record with unknown density because the sampled raster value is null. The saved final selection artifact contains the 53 over-threshold original facility records with benchmark_row_id and point geometry.

Recorded workflow

  1. 01

    Algeria facilities

    Recorded vector-filter · succeeded

  2. 02

    Algeria facilities with sampled population density

    Recorded output · succeeded

  3. 03

    Algeria facilities with unknown sampled density

    Recorded output · succeeded

  4. 04

    Algeria facilities over 1000 people per square kilometre

    Recorded output · succeeded

  5. 05

    Supplied density raster

    Recorded source · succeeded

  6. 06

    Supplied facilities

    Recorded source · succeeded

  7. 07

    Over-threshold facilities

    Recorded vector-filter · succeeded

  8. 08

    Sample density

    Recorded raster-sample · succeeded

  9. 09

    Unknown-density facilities

    Recorded vector-filter · succeeded

  10. 10

    Algeria facilities

    Recorded vector-filter · succeeded

  11. 11

    Supplied density raster

    Recorded source · succeeded

  12. 12

    Supplied facilities

    Recorded source · succeeded

  13. 13

    Sample density

    Recorded raster-sample · succeeded

  14. 14

    Algeria facilities

    Recorded output · succeeded

  15. 15

    Sample density

    Recorded output · succeeded

Activity

Recorded actions

Recorded observable actions only, not private reasoning. Raw payloads, geometry, private links and credentials are omitted; full evidence is retained privately. Activity/workflow lists bounded at 500 entries.

  1. Progress update

    I’ll check the two supplied fixtures, confirm the facility fields and raster coverage, then run a small private computation that filters Algeria facilities, samples the WorldPop 2020 pixel at each point, and saves the selected records as an inspectable artifact.

  2. Progress update

    I found the Blue analysis tools. Next I’m reading the two supplied fixtures so I can use their exact field names and item selections, then I’ll choose the smallest sampling workflow that preserves original Algeria facility records.

  3. get_analysis

    Recorded tool call · completed

  4. get_collection

    Recorded tool call · completed

  5. get_collection

    Recorded tool call · completed

  6. get_item

    Recorded tool call · completed

  7. get_item

    Recorded tool call · completed

  8. inspect_artifact

    Recorded tool call · failed

  9. inspect_artifact

    Recorded tool call · failed

  10. list_processors

    Recorded tool call · completed

  11. list_processors

    Recorded tool call · completed

  12. list_processors

    Recorded tool call · completed

  13. list_processors

    Recorded tool call · completed

  14. get_tool_help

    Recorded tool call · completed

  15. get_tool_help

    Recorded tool call · completed

  16. describe_processors

    Recorded tool call · completed

  17. Progress update

    I’ve confirmed the fixtures and the needed field names. The key remaining method choice is how to sample the exact containing pixel and then count selected versus unknown records without changing the original point rows. I’m reading the exact processor schemas before I test that path.

  18. get_tool_help

    Recorded tool call · completed

  19. get_tool_help

    Recorded tool call · completed

  20. get_tool_help

    Recorded tool call · completed

  21. get_tool_help

    Recorded tool call · completed

  22. get_tool_help

    Recorded tool call · completed

  23. get_tool_help

    Recorded tool call · completed

  24. update_analysis_brief

    Recorded tool call · completed

  25. run_trial

    Recorded tool call · completed

  26. Progress update

    The sampling trial finished successfully. It showed 139 Algeria facility records, preserved benchmark_row_id and geometry, and wrote the sampled raster value into a field named `density` with 1 null record for unknown coverage. I’m now turning that tested path into the final saved workflow that outputs the over-threshold selection artifact and a separate unknown selection for counting.

  27. get_trial_report

    Recorded tool call · completed

  28. assess_trial

    Recorded tool call · completed

  29. get_tool_help

    Recorded tool call · completed

  30. get_tool_help

    Recorded tool call · completed

  31. Progress update

    The trial answered the key uncertainty, so I’ve updated the method: use the sampled `density` field directly, treat null as unknown, and save three outputs from the final run — the full sampled Algeria set for verification, the strict `density > 1000` selection, and the unknown-density selection. Then I’ll inspect those outputs and record the final count.

  32. update_analysis_brief

    Recorded tool call · completed

  33. get_tool_help

    Recorded tool call · completed

  34. propose_workflow

    Recorded tool call · completed

  35. Progress update

    The final workflow is saved and validated. It reuses the tested Algeria filter and sampling steps, then adds only the two untested but simple final filters: `density > 1000` and `density is null`. I’m executing that exact workflow now and will inspect the three saved outputs before I give the count.

  36. execute_workflow

    Recorded tool call · completed

  37. inspect_workflow_results

    Recorded tool call · completed

  38. Progress update

    The run finished in the background while the turn was interrupted. I’m inspecting the saved outputs now to verify the exact counts, confirm benchmark_row_id is preserved on the selected records, and then I’ll record the final answer object against those inspected artifacts.

  39. Progress update

    I have the exact output counts from the completed run: 53 over the threshold and 1 unknown. I’m doing one bounded inspection of the selected and unknown artifacts now so the final assessment cites the saved artifact identity and confirms benchmark_row_id is present with the original point geometry.

  40. inspect_artifact

    Recorded tool call · completed

  41. inspect_artifact

    Recorded tool call · completed

  42. inspect_artifact

    Recorded tool call · completed

  43. Progress update

    The run results are already in hand. I’m refreshing the bounded artifact inspections now so the final assessment cites the inspected selection and supporting outputs directly, then I’ll record the accepted result.

  44. inspect_artifact

    Recorded tool call · completed

  45. inspect_artifact

    Recorded tool call · completed

  46. inspect_artifact

    Recorded tool call · completed

  47. Progress update

    I’ve finished the bounded inspections. They confirm the saved over-threshold artifact has 53 records with unique benchmark_row_id values and point geometry, the unknown artifact has 1 null-density record, and the full sampled Algeria artifact has 139 records with 1 null density. I’m updating the brief notes and recording the accepted final result now.

  48. update_analysis_brief

    Recorded tool call · completed

  49. assess_result

    Recorded tool call · completed

|||

© 2026 Exia Labs, Inc.