Research/Terra/ 365343
Task evidence / forest-river-intersection

River records intersecting highly forested South American countries

PassComputational taskUnpublished draft
Download evidence JSON ↓

The question

365343
How many rivers flow through areas with significant forest coverage in South America?
Exact submitted task and declared adaptations
How many rivers flow through areas with significant forest coverage in South America?

Task conventions: Use the released reference's country-level definition: South American countries (CONTINENT='South America') with World Bank 2021 forest area strictly greater than 50 percent of land area. Join original ISO_A3 to Country Code, not fuzzy names. Count distinct original FAO river records intersecting those polygons, including boundary touches. A record can meet several countries but counts once; these are river segments, not unique named whole rivers. National forest percentage is NOT a map of actual forest along a river. Keep unknown/missing indicator countries explicit; unknown_count is the number of river records that intersect an unknown eligible country and no qualifying known country, plus invalid/missing river geometries. Use the original frozen data, no live substitution. This is internal research; FAO-derived outputs are not cleared for promotional publication.



Return the original selected river features with benchmark_row_id, attributes and unchanged geometry. Map optional. Finish with fenced JSON {count:integer,unknown_count:integer,coverage_note:string,selection:{collectionId,itemId,assetKey}}. Explain the country-level proxy, 2021 year and segment-count unit.

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": "FAO AQUAmaps South American river segments",
    "edition": "Frozen regional HydroSHEDS-derived rivers_samerica_37330; internal research only, no promotional sharing",
    "units": {},
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  },
  {
    "name": "World Bank country boundaries",
    "edition": "GeoBenchX harmonized names",
    "units": {},
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  },
  {
    "name": "World Bank AG.LND.FRST.ZS",
    "edition": "Frozen GeoBenchX World Development Indicators; use 2021",
    "units": {
      "2021": "% of land area"
    },
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  }
]

Outcome & verification

Independent artifact and delivery checks passed.

Duration
33m 22s
Recorded Blue tool calls
61
Total tokens
3,104,836
Model cost
Not recorded
Application revision
d50497ea9084f29c91b05406688f87035df98d8a
Release
terra-geobenchx-v1

Recorded final answer

I found **66,314** qualifying river segments in the final selected dataset, with **unknown_count = 16**. This uses the supplied frozen World Bank **2021** country-level forest percentage joined exactly from **ISO_A3** to **Country Code**. It counts distinct FAO **river segment records**, not whole named rivers, and the forest measure is a **country-level proxy**, not forest mapped along each segment. The FAO-derived output is for **internal research only**. ### Limitations - The forest criterion is a country-level 2021 proxy, not mapped forest along each river segment. - The FAO-derived river source is for internal research only and is not cleared for promotional publication. - The forest criterion is a country-level 2021 proxy, not mapped forest cover along each river segment. - These counted records are FAO river segments, not unique named whole rivers. - unknown_count reflects segments intersecting the explicit unmatched FLK country row and 0 invalid or missing river geometries in this frozen run. - FAO-derived outputs are for internal research only and are not cleared for promotional publication. - Boundary membership defines South America here, but it does not by itself establish forest eligibility. - National 2021 forest percentage is a country-level proxy, not measured forest along each river segment. - Distinct records are river segments, not deduplicated named whole rivers.

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
66314
Reported count
66314
Computation verified
Yes
Answer fulfilled
Yes
Full grading and rubric record
{
  "expectedCount": 66314,
  "actualCount": 66314,
  "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 · failed

Does the full-scope ISO_A3-to-Country Code workflow produce the required distinct South America river-segment selection, with qualifying and unknown countries handled separately and invalid river geometries preserved for unknown_count?

run_trial · completed

Does the full-scope ISO_A3-to-Country Code workflow produce the required distinct South America river-segment selection, with qualifying and unknown countries handled separately and invalid river geometries preserved for unknown_count?

assess_trial · completed · assessment: sufficient

The full-scope trial answered the method question. Filtering the supplied boundaries to CONTINENT='South America' produced 13 country records. Joining boundary ISO_A3 to forest-table Country Code matched 12 records and left one explicit unmatched country, FLK (Falkland Islands), with null 2021 forest indicator. Filtering joined countries on 2021 forest area strictly greater than 50 percent produced 7 qualifying countries. Aggregating qualifying and unknown country flags onto valid river segments with an intersects spatial join preserved one row per original valid river segment across the full supplied river dataset (100,557 rows). The qualifying selection contains 66,314 distinct original river segment records. The unknown-only valid selection contains 16 river segment records that intersect the unknown country and no qualifying known country. The invalid or missing river-geometry branch contains 0 records. The counted river output preserves benchmark_row_id, original river attributes, and unchanged target river geometry while adding diagnostic fields for the join.

assess_result · completed · assessment: sufficient

Using only the supplied frozen datasets, the executed final workflow counted 66,314 distinct original FAO river segment records intersecting South American country polygons whose frozen World Bank AG.LND.FRST.ZS 2021 forest area is strictly greater than 50 percent of land area after an exact ISO_A3-to-Country Code join. The executed final selection artifact preserves benchmark_row_id, original river attributes, and unchanged line geometry while also carrying workflow diagnostic fields. unknown_count is 16: 16 segments intersect only the explicit unknown country row (Falkland Islands, FLK) and the executed invalid-geometry count is 0. This is a country-level 2021 proxy, not forest along each river segment, and the unit is river segments rather than unique named whole rivers.

Recorded workflow

  1. 01

    Counted river segments

    Recorded vector-filter · succeeded

  2. 02

    Join 2021 forest indicator to countries

    Recorded table-attribute-join · succeeded

  3. 03

    Supplied country boundaries

    Recorded source · succeeded

  4. 04

    Qualifying river segments

    Recorded output · succeeded

  5. 05

    Qualifying river segment count

    Recorded output · succeeded

  6. 06

    Unknown-only river segment count

    Recorded output · succeeded

  7. 07

    Invalid river geometry count

    Recorded output · succeeded

  8. 08

    Qualifying countries over 50 percent forest

    Recorded vector-filter · succeeded

  9. 09

    Flag qualifying countries

    Recorded vector-field-calculate · succeeded

  10. 10

    Merge qualifying and unknown country flags

    Recorded vector-merge · succeeded

  11. 11

    Supplied WDI forest table

    Recorded source · succeeded

  12. 12

    Invalid river geometry count

    Recorded table-group-statistics · succeeded

  13. 13

    Known qualifying river count

    Recorded table-group-statistics · succeeded

  14. 14

    Aggregate country matches onto rivers

    Recorded vector-spatial-join · succeeded

  15. 15

    Invalid or missing river geometries

    Recorded vector-filter · succeeded

  16. 16

    Preserve invalid river geometries as unknown

    Recorded vector-measure · succeeded

  17. 17

    Supplied FAO river segments

    Recorded source · succeeded

  18. 18

    Valid river geometries

    Recorded vector-filter · succeeded

  19. 19

    South America countries

    Recorded vector-filter · succeeded

  20. 20

    Rivers touching unknown countries

    Recorded vector-filter · succeeded

  21. 21

    Unknown forest indicator countries

    Recorded vector-filter · succeeded

  22. 22

    Flag unknown countries

    Recorded vector-field-calculate · succeeded

  23. 23

    Unknown-only valid river count

    Recorded table-group-statistics · succeeded

  24. 24

    Unknown-only valid rivers

    Recorded vector-filter · succeeded

  25. 25

    Counted river segments

    Recorded vector-filter · succeeded

  26. 26

    Join 2021 forest indicator to countries

    Recorded table-attribute-join · succeeded

  27. 27

    Supplied country boundaries

    Recorded source · succeeded

  28. 28

    Qualifying countries over 50 percent forest

    Recorded vector-filter · succeeded

  29. 29

    Flag qualifying countries

    Recorded vector-field-calculate · succeeded

  30. 30

    Merge qualifying and unknown country flags

    Recorded vector-merge · succeeded

  31. 31

    Supplied WDI forest table

    Recorded source · succeeded

  32. 32

    Invalid river geometry count

    Recorded table-group-statistics · succeeded

  33. 33

    Known qualifying river count

    Recorded table-group-statistics · succeeded

  34. 34

    Aggregate country matches onto rivers

    Recorded vector-spatial-join · succeeded

  35. 35

    Invalid or missing river geometries

    Recorded vector-filter · succeeded

  36. 36

    Preserve invalid river geometries as unknown

    Recorded vector-measure · succeeded

  37. 37

    Supplied FAO river segments

    Recorded source · succeeded

  38. 38

    Valid river geometries

    Recorded vector-filter · succeeded

  39. 39

    South America countries

    Recorded vector-filter · succeeded

  40. 40

    Join 2021 forest indicator to countries

    Recorded output · succeeded

  41. 41

    Invalid river geometry count

    Recorded output · succeeded

  42. 42

    Qualifying countries over 50 percent forest

    Recorded output · succeeded

  43. 43

    Unknown forest indicator countries

    Recorded output · succeeded

  44. 44

    Aggregate country matches onto rivers

    Recorded output · succeeded

  45. 45

    Counted river segments

    Recorded output · succeeded

  46. 46

    Unknown-only valid rivers

    Recorded output · succeeded

  47. 47

    Invalid or missing river geometries

    Recorded output · succeeded

  48. 48

    Known qualifying river count

    Recorded output · succeeded

  49. 49

    Unknown-only valid river count

    Recorded output · succeeded

  50. 50

    Rivers touching unknown countries

    Recorded vector-filter · succeeded

  51. 51

    Unknown forest indicator countries

    Recorded vector-filter · succeeded

  52. 52

    Flag unknown countries

    Recorded vector-field-calculate · succeeded

  53. 53

    Unknown-only valid river count

    Recorded table-group-statistics · succeeded

  54. 54

    Unknown-only valid rivers

    Recorded vector-filter · 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’m checking the saved analysis context and the exact source schemas first, then I’ll test the country join and river count with the frozen inputs you supplied.

  2. get_analysis

    Recorded tool call · completed

  3. Progress update

    I found no saved analysis yet. Next I’m reading the three frozen datasets to confirm the exact fields for South America, ISO_A3, Country Code, the 2021 forest indicator, and the river row ID/geometry handling before I test the count.

  4. get_collection

    Recorded tool call · completed

  5. get_collection

    Recorded tool call · completed

  6. get_collection

    Recorded tool call · completed

  7. get_item

    Recorded tool call · completed

  8. get_item

    Recorded tool call · completed

  9. get_item

    Recorded tool call · completed

  10. Progress update

    I confirmed the three sources are the exact frozen benchmark inputs. Now I’m pulling bounded samples and item metadata so I can use the original key fields instead of guessing column names.

  11. Progress update

    I have the exact columns now. Next I’m sampling the South America country rows and the 2021 forest table so I can verify which ISO_A3 codes qualify, which are unknown, and how many river records may need the unknown bucket.

  12. inspect_artifact

    Recorded tool call · failed

  13. inspect_artifact

    Recorded tool call · failed

  14. get_tool_help

    Recorded tool call · completed

  15. get_collection

    Recorded tool call · failed

  16. get_collection

    Recorded tool call · failed

  17. get_collection

    Recorded tool call · completed

  18. get_collection

    Recorded tool call · completed

  19. list_processors

    Recorded tool call · completed

  20. list_processors

    Recorded tool call · completed

  21. list_processors

    Recorded tool call · completed

  22. list_processors

    Recorded tool call · completed

  23. describe_processors

    Recorded tool call · completed

  24. get_tool_help

    Recorded tool call · completed

  25. get_tool_help

    Recorded tool call · completed

  26. get_tool_help

    Recorded tool call · completed

  27. describe_processors

    Recorded tool call · completed

  28. describe_processors

    Recorded tool call · completed

  29. describe_processors

    Recorded tool call · completed

  30. get_tool_help

    Recorded tool call · completed

  31. Progress update

    I’ve confirmed the exact join keys and the immutable source editions. I’m recording the brief now, then I’ll run one end-to-end private test that checks the join, the unknown-country bucket, invalid river geometries, and the distinct segment count on the requested full South America scope.

  32. update_analysis_brief

    Recorded tool call · completed

  33. describe_processors

    Recorded tool call · completed

  34. Progress update

    I’ve built the trial method. It uses the exact frozen items, filters South America from the supplied boundary layer, joins ISO_A3 to Country Code, marks qualifying and unknown countries separately, runs one aggregated river-to-country spatial join so each river stays a single row, and keeps invalid river geometries separate for the unknown bucket. Now I’m running that full-scope private test and inspecting both the country classification and the resulting river selections.

  35. run_trial

    Recorded tool call · failed

  36. Progress update

    The first submission had a CRS argument typo. I’m correcting that and rerunning the same trial; the method itself is unchanged.

  37. run_trial

    Recorded tool call · completed

  38. get_analysis

    Recorded tool call · completed

  39. Progress update

    The brief stored the scope CRS in a non-canonical form, which is why the trial was blocked. I’m fixing the saved study extent to the accepted CRS84 label and then rerunning the same full-scope test.

  40. update_analysis_brief

    Recorded tool call · completed

  41. Progress update

    The private full-scope test finished in the background. It worked: the exact ISO_A3 join matched 12 of 13 South America boundary records, leaving Falkland Islands (FLK) explicit as the one unknown country; 7 countries qualified at >50% forest in 2021; 66,314 river segments intersect a qualifying country; 16 intersect only the unknown country; and there were 0 invalid or missing river geometries. I’m recording that test result now, then I’ll save and run the final workflow that delivers the counted river selection and the answer fields.

  42. assess_trial

    Recorded tool call · completed

  43. get_tool_help

    Recorded tool call · completed

  44. get_tool_help

    Recorded tool call · completed

  45. get_tool_help

    Recorded tool call · completed

  46. get_tool_help

    Recorded tool call · completed

  47. get_tool_help

    Recorded tool call · completed

  48. Progress update

    I’m checking a few exact rows from the finished trial now: the qualifying country list, the unknown country row, and sample counted river rows. That lets me cite the eligible countries cleanly and confirm the delivered river selection still carries benchmark_row_id and the original river attributes.

  49. inspect_artifact

    Recorded tool call · completed

  50. inspect_artifact

    Recorded tool call · completed

  51. inspect_artifact

    Recorded tool call · completed

  52. get_tool_help

    Recorded tool call · completed

  53. get_tool_help

    Recorded tool call · completed

  54. get_tool_help

    Recorded tool call · completed

  55. Progress update

    The finished trial rows are ready now. I’m pulling the exact qualifying-country list, the single unknown country row, and sample counted river rows, then I’ll save the tested workflow as the final run and bind the result.

  56. inspect_artifact

    Recorded tool call · completed

  57. inspect_artifact

    Recorded tool call · completed

  58. inspect_artifact

    Recorded tool call · completed

  59. Progress update

    The method is now verified on the full frozen study area. I’m refreshing the brief to remove stale preparation notes, then I’ll save the exact tested computation as the final workflow and inspect its outputs.

  60. update_analysis_brief

    Recorded tool call · completed

  61. get_tool_help

    Recorded tool call · completed

  62. Progress update

    I’ve got a tested computation with full-area evidence. I’m saving that exact method as the final workflow now, with the counted river selection as the main deliverable and the count tables as supporting outputs for the final answer binding.

  63. propose_workflow

    Recorded tool call · completed

  64. execute_workflow

    Recorded tool call · completed

  65. Progress update

    The saved workflow matches the tested computation and is ready. I’m starting that exact run now so I can inspect its final artifacts and record the answer against executed outputs rather than the private trial.

  66. Progress update

    The final workflow finished in the background. I’m inspecting its exact outputs now so I can bind the accepted answer to the executed final artifacts rather than the private trial.

  67. inspect_workflow_results

    Recorded tool call · completed

  68. Progress update

    The final run completed. I’m doing the last bounded checks on the executed outputs now: the selected river artifact itself and the three supporting count tables. Then I’ll record the final machine-readable answer against those exact final artifacts.

  69. inspect_artifact

    Recorded tool call · completed

  70. inspect_artifact

    Recorded tool call · completed

  71. inspect_artifact

    Recorded tool call · completed

  72. Progress update

    The final workflow run is complete. I’m fetching the finished inspection receipts for the qualifying river selection and the supporting count tables now, then I’ll record the final answer object against those executed artifacts.

  73. inspect_artifact

    Recorded tool call · completed

  74. inspect_artifact

    Recorded tool call · completed

  75. inspect_artifact

    Recorded tool call · completed

  76. inspect_artifact

    Recorded tool call · completed

  77. Progress update

    I’ve got the executed selection and the two count tables. I’m pulling the last supporting table now — invalid river geometry count — and then I’ll record the final accepted answer against the final workflow outputs.

  78. inspect_artifact

    Recorded tool call · completed

  79. Progress update

    I’ve verified the executed final outputs: the selected qualifying river-segment artifact has 66,314 distinct benchmark_row_id values, the unknown-only count table has 16, and the invalid-geometry count table has 0. I’m recording the final answer now with the executed selection artifact attached.

  80. assess_result

    Recorded tool call · completed

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