Research/Terra/ 645898
Task evidence / water-feature-selection

Counties touching the Mississippi River

PassComputational taskUnpublished draft
Download evidence JSON ↓

The question

645898
List and make a map of all counties that touch or include the Mississippi River
Exact submitted task and declared adaptations
List and make a map of all counties that touch or include the Mississippi River

Task conventions: Use the original CEC 2023 river geometries where NameEn equals 'Mississippi River', not tributaries or similarly named rivers. Select original 2024 county polygons intersecting any selected river line, including boundary touches. Compare in the county source CRS; no buffer, simplification or clipping. Duplicate river matches count each original county once. These are intersections between generalized river/cartographic county sources, not surveyed legal shoreline determinations. Unknown_count counts missing/invalid county geometries; do not silently treat them as no intersection. Keep source editions and all original IDs. Supplied water data is for this internal benchmark only.



Return an inspectable selected-feature artifact preserving original attributes, geometry and benchmark_row_id. End with one fenced JSON object: {count:integer,unknown_count:integer,coverage_note:string,selection:{collectionId,itemId,assetKey}}. List county names and state/GEOID, add the selected counties to this map, and include map_layer_id in that JSON.

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": "US county boundaries",
    "edition": "Census TIGER/Line 2024",
    "units": {},
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  },
  {
    "name": "North American rivers, CEC 2023 frozen benchmark source",
    "edition": "CEC North American Environmental Atlas version 4.0 (2023), original benchmark snapshot; benchmark-only use",
    "units": {},
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  }
]

Outcome & verification

Independent artifact and delivery checks passed.

Duration
17m 53s
Recorded Blue tool calls
60
Total tokens
2,259,773
Model cost
Not recorded
Application revision
d50497ea9084f29c91b05406688f87035df98d8a
Release
terra-geobenchx-v1

Recorded final answer

I found 115 counties touching the benchmark Mississippi River and added them to the map. Unknown_count is 0. The accepted result includes the inspectable selected artifact, the full county list with state/GEOID, and map layer `[resource id withheld]`. Sources: CEC North American Environmental Atlas v4.0 (2023) benchmark river snapshot and Census TIGER/Line 2024 benchmark county snapshot, inspected 2026-10-07. These are generalized river/cartographic county intersections, not surveyed legal shoreline determinations. ### Limitations - These are intersections between generalized river and cartographic county sources, not surveyed legal shoreline determinations. - The result reflects the supplied benchmark editions only: CEC North American Environmental Atlas v4.0 (2023) rivers and Census TIGER/Line 2024 counties. - This source is generalized cartography, not a legal shoreline record. - This is a cartographic source intersection, not a surveyed legal shoreline determination. - The displayed map layer is a view of the selected artifact; it does not change the selection logic.

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
115
Reported count
115
Computation verified
Yes
Answer fulfilled
Yes
Full grading and rubric record
{
  "expectedCount": 115,
  "actualCount": 115,
  "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

Do the supplied river and county datasets expose the exact fields needed for a Mississippi River filter and a county selection artifact with preserved IDs and geometry?

assess_trial · completed · assessment: sufficient

The supplied river dataset exposes NameEn and benchmark_row_id, and the supplied county dataset exposes NAME, STATEFP, GEOID, GEOIDFQ, COUNTYFP, COUNTYNS, and benchmark_row_id. The inspection also shows both source geometries in EPSG:4326 and reports county invalidCount 0 for the full supplied county set, so the datasets are suitable for an exact-name river filter and county-preserving spatial selection.

run_trial · completed

Does the exact-name Mississippi River filter plus an intersects aggregate join select the correct one-row-per-county county set nationwide without buffering, simplification, or clipping?

assess_trial · completed · assessment: sufficient

The exact river filter returned one feature with NameEn = Mississippi River and benchmark_row_id = na_rivers:005164. The exact county selection used an inner aggregate spatial join with predicate = intersects and returned 115 rows, each preserving original county fields, geometry, and benchmark_row_id. The join reported inputTargetRecords = 3235, targetFeatures = 3235, targetRecordsOmittedBeforeJoin = 0, and matchedTargetFeatures = 115, which supports one-row-per-county selection with no duplicate county rows and no invalid or empty county geometries excluded before the join.

assess_result · completed · assessment: sufficient

I delivered an inspectable selected-feature artifact for the counties that touch or include the supplied benchmark Mississippi River line and added that artifact to the current map. The final selected artifact contains 115 county records, preserves original county identifiers and benchmark_row_id, and the final join evidence supports unknown_count = 0.

Recorded workflow

  1. 01

    Supplied counties

    Recorded source · succeeded

  2. 02

    Counties touching the Mississippi River

    Recorded output · succeeded

  3. 03

    Filter Mississippi River

    Recorded vector-filter · succeeded

  4. 04

    Supplied rivers

    Recorded source · succeeded

  5. 05

    Select counties touching river

    Recorded vector-spatial-join · succeeded

  6. 06

    Supplied counties

    Recorded source · succeeded

  7. 07

    Filter Mississippi River

    Recorded vector-filter · succeeded

  8. 08

    Supplied rivers

    Recorded source · succeeded

  9. 09

    Select counties touching river

    Recorded vector-spatial-join · succeeded

  10. 10

    Filter Mississippi River

    Recorded output · succeeded

  11. 11

    Select counties touching river

    Recorded output · succeeded

  12. 12

    Supplied counties

    Recorded source · succeeded

  13. 13

    Supplied rivers

    Recorded source · succeeded

  14. 14

    Supplied rivers

    Recorded output · succeeded

  15. 15

    Supplied counties

    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’m checking the saved analysis context and the exact Blue tool schemas first, then I’ll run a small private test before building the final county selection and map layer.

  2. get_analysis

    Recorded tool call · completed

  3. get_map_context

    Recorded tool call · completed

  4. get_tool_help

    Recorded tool call · completed

  5. get_tool_help

    Recorded tool call · completed

  6. get_tool_help

    Recorded tool call · completed

  7. list_processors

    Recorded tool call · completed

  8. get_collection

    Recorded tool call · completed

  9. get_tool_help

    Recorded tool call · completed

  10. get_collection

    Recorded tool call · completed

  11. get_tool_help

    Recorded tool call · completed

  12. Progress update

    I’ve got the tool schemas and there’s no saved work yet. Next I’m inspecting the two supplied datasets and looking up the safest processors for a no-buffer county/river intersection in the county source CRS.

  13. Progress update

    I found the likely path: filter the supplied river lines to `NameEn = Mississippi River`, then do a polygon-line spatial join that keeps each original county once. I’m checking the exact processor contracts now so I can test the no-buffer, county-CRS method without guessing fields or join behavior.

  14. describe_processors

    Recorded tool call · completed

  15. describe_processors

    Recorded tool call · completed

  16. get_tool_help

    Recorded tool call · completed

  17. update_analysis_brief

    Recorded tool call · completed

  18. Progress update

    I’ve saved the goal and acceptance checks. Now I’m running a tiny private inspection so I can read the exact field names and output schema before the real intersection.

  19. run_trial

    Recorded tool call · completed

  20. Progress update

    The source check succeeded in the background. I confirmed both supplied datasets carry `benchmark_row_id`, the river has `NameEn`, the counties have `NAME`, `STATEFP`, and `GEOID`, and both geometries are in EPSG:4326. Next I’m testing the real selection method nationwide: exact river-name filter, then one-row-per-county intersects join with no buffer or clipping.

  21. assess_trial

    Recorded tool call · completed

  22. run_trial

    Recorded tool call · completed

  23. Progress update

    The method test finished cleanly: one exact river feature, 115 matched counties, and no duplicated county rows. I’m turning that tested computation into the final deliverable now, then I’ll inspect the finished artifact, add it to the map, and report the county list.

  24. get_trial_report

    Recorded tool call · completed

  25. inspect_workflow_results

    Recorded tool call · completed

  26. get_tool_help

    Recorded tool call · completed

  27. get_tool_help

    Recorded tool call · completed

  28. get_tool_help

    Recorded tool call · completed

  29. get_tool_help

    Recorded tool call · completed

  30. get_tool_help

    Recorded tool call · completed

  31. get_tool_help

    Recorded tool call · completed

  32. get_tool_help

    Recorded tool call · completed

  33. get_tool_help

    Recorded tool call · completed

  34. assess_trial

    Recorded tool call · completed

  35. update_analysis_brief

    Recorded tool call · completed

  36. Progress update

    I’ve got a tested full-area method now. I’m saving that exact method as the final workflow so the delivered artifact matches the verified trial, then I’ll inspect the final county table, add it as a map layer, and package the answer object.

  37. propose_workflow

    Recorded tool call · completed

  38. execute_workflow

    Recorded tool call · completed

  39. Progress update

    The saved workflow appears to have completed in the background. I’m inspecting the final delivered output now, then I’ll bind that exact artifact to the map and record the result object.

  40. list_map_layers

    Recorded tool call · completed

  41. inspect_workflow_results

    Recorded tool call · completed

  42. get_analysis

    Recorded tool call · completed

  43. inspect_artifact

    Recorded tool call · completed

  44. inspect_artifact

    Recorded tool call · completed

  45. Progress update

    I have the final artifact identity and the live map layer. I’m doing one bounded inspection of the delivered county layer for the county list and schema, plus a fresh county-source check for invalid geometry, so the final answer can include the exact count, unknown_count, and selected artifact reference.

  46. inspect_artifact

    Recorded tool call · completed

  47. inspect_artifact

    Recorded tool call · completed

  48. inspect_artifact

    Recorded tool call · completed

  49. inspect_artifact

    Recorded tool call · completed

  50. inspect_artifact

    Recorded tool call · completed

  51. inspect_artifact

    Recorded tool call · completed

  52. inspect_artifact

    Recorded tool call · completed

  53. inspect_artifact

    Recorded tool call · completed

  54. inspect_artifact

    Recorded tool call · completed

  55. Progress update

    I’m checking the exact `assess_result` input format before I lock the final answer, so I use the right artifact reference and answer object fields.

  56. inspect_artifact

    Recorded tool call · completed

  57. inspect_artifact

    Recorded tool call · completed

  58. get_tool_help

    Recorded tool call · completed

  59. Progress update

    I’m retrieving the two county-list pages and the county-source validity summary now. That will give me the full 115-county list plus the explicit unknown_count from the supplied county source.

  60. inspect_artifact

    Recorded tool call · completed

  61. inspect_artifact

    Recorded tool call · completed

  62. inspect_artifact

    Recorded tool call · completed

  63. Progress update

    The row pages are retained as evidence receipts. I’m reading those bounded pages directly now.

  64. read_evidence

    Recorded tool call · completed

  65. read_evidence

    Recorded tool call · completed

  66. read_evidence

    Recorded tool call · completed

  67. Progress update

    The default evidence page is tiny. I’m pulling larger pages so I can extract the full county list and the county invalid-geometry count.

  68. read_evidence

    Recorded tool call · completed

  69. read_evidence

    Recorded tool call · completed

  70. read_evidence

    Recorded tool call · completed

  71. Progress update

    I’ve got the first chunk of both county-list pages. I’m reading the remaining chunks now so the final county list is complete.

  72. read_evidence

    Recorded tool call · completed

  73. read_evidence

    Recorded tool call · completed

  74. Progress update

    I’m recording the verified final result now: the inspected selected artifact, count, unknown_count, full county list, and the live map layer ID.

  75. assess_result

    Recorded tool call · completed

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