Research/Terra/ 883928
Task evidence / spatial-analysis

Snow-exposed Amtrak stations by state

PassComputational taskUnpublished draft
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The question

883928
Which US states have the highest number of Amtrak stations in snow-covered areas (>1 foot)?
Exact submitted task and declared adaptations
Which US states have the highest number of Amtrak stations in snow-covered areas (>1 foot)?

Task conventions: Use the supplied frozen 2024–25 snowfall raster in inches and the pixel containing each station. Strictly greater than 12 inches qualifies; zero is valid, NoData/outside raster is unknown. Use each station's supplied State attribute to group the 50 US states, rather than reassigning its location to a new geography. Count original station records once by benchmark_row_id. Give all positive state counts in descending order, retaining ties; do not substitute unique state names for station counts. Non-US province codes and DC are outside this state comparison. Maps are optional.



Produce an inspectable selected-station data artifact retaining original geometry, benchmark_row_id, State and sampled snowfall, plus the computed state comparison. End with one fenced JSON object: {count: total selected US station records, unknown_count: eligible US records with unknown snow, coverage_note: string, selection: {collectionId, itemId, assetKey}, groups: {state_code: integer_count}, value_field: name_of_sampled_snowfall_column_in_selection}. Include all positive groups, not just the largest. These field names are mandatory for grading, but choose your own valid workflow.

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": "Amtrak railway stations",
    "edition": "USDOT BTS frozen GeoBenchX 2025 snapshot",
    "units": {},
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  },
  {
    "name": "US snowfall, 2024\u201325 frozen season",
    "edition": "2024-09-30 to 2025-05-20",
    "units": {
      "band1": "inches"
    },
    "collectionId": "blue-generated--[resource id withheld]",
    "itemId": "[resource id withheld]",
    "assetKey": "data"
  }
]

Outcome & verification

Independent artifact and delivery checks passed.

Duration
14m 35s
Recorded Blue tool calls
40
Total tokens
2,853,777
Model cost
Not recorded
Application revision
d50497ea9084f29c91b05406688f87035df98d8a
Release
terra-geobenchx-v1

Recorded final answer

Michigan has the most qualifying Amtrak stations: 55. Then Pennsylvania 50, New York 41, Wisconsin 38, and Oregon 33. Across the 50-state comparison, 530 station records were in pixels with snowfall strictly greater than 12 inches, and 36 eligible US records had unknown snowfall, so they were kept out of the positive counts. I attached the inspectable selected-station artifact with `snowfall_in`. Sources: Amtrak / USDOT BTS frozen GeoBenchX 2025 snapshot; NOAA/NWS NOHRSC frozen 2024–25 snowfall raster (2024-09-30 to 2025-05-20), retrieved in this run on 2026-10-07. ### Limitations - Eligible US stations with NoData or outside-raster snowfall remain unknown and are reported separately, not counted as selected. - Eligible US stations with unknown snowfall are excluded because they cannot be confirmed above 12 inches. - Eligible US stations with unknown snowfall remain separate and are not included in these counts. - The selected-station result excludes unknown snowfall rows because they cannot be confirmed above the threshold. - Null sampled values remain unknown because NoData or outside-raster locations cannot be treated as zero. - DC and non-US province codes are outside this comparison by design. - Unknown snowfall rows stay outside the positive counts until confirmed.

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
530
Reported count
530
Computation verified
Yes
Answer fulfilled
Yes
Full grading and rubric record
{
  "expectedCount": 530,
  "actualCount": 530,
  "expectedMetrics": {
    "AR": 1,
    "AZ": 4,
    "CA": 21,
    "CO": 19,
    "CT": 15,
    "IA": 3,
    "ID": 3,
    "IL": 24,
    "IN": 10,
    "KS": 7,
    "KY": 4,
    "MA": 13,
    "MD": 15,
    "ME": 15,
    "MI": 55,
    "MN": 9,
    "MO": 13,
    "MT": 12,
    "ND": 7,
    "NE": 5,
    "NH": 11,
    "NJ": 6,
    "NM": 8,
    "NV": 1,
    "NY": 41,
    "OH": 6,
    "OR": 33,
    "PA": 50,
    "RI": 4,
    "UT": 5,
    "VA": 18,
    "VT": 24,
    "WA": 16,
    "WI": 38,
    "WV": 10,
    "WY": 4
  },
  "actualMetrics": {
    "AR": 1,
    "AZ": 4,
    "CA": 21,
    "CO": 19,
    "CT": 15,
    "IA": 3,
    "ID": 3,
    "IL": 24,
    "IN": 10,
    "KS": 7,
    "KY": 4,
    "MA": 13,
    "MD": 15,
    "ME": 15,
    "MI": 55,
    "MN": 9,
    "MO": 13,
    "MT": 12,
    "ND": 7,
    "NE": 5,
    "NH": 11,
    "NJ": 6,
    "NM": 8,
    "NV": 1,
    "NY": 41,
    "OH": 6,
    "OR": 33,
    "PA": 50,
    "RI": 4,
    "UT": 5,
    "VA": 18,
    "VT": 24,
    "WA": 16,
    "WI": 38,
    "WV": 10,
    "WY": 4
  },
  "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 sampling the supplied snowfall raster onto the supplied Amtrak stations retain one row per station with benchmark_row_id and State, and what sampled snowfall field name and null behavior should the final workflow use?

assess_trial · completed · assessment: sufficient

Sampling the supplied snowfall raster onto the supplied station points produced 1,020 point records and preserved the original station fields, including benchmark_row_id and State. The sampled snowfall field name is snowfall_in, with valid values ranging from 0.0 to 372.04315185546875 inches and 52 null values representing unknown snowfall from NoData or outside-raster locations. Grouping the sampled output by benchmark_row_id returned 1,020 distinct IDs and row_count=1 for every grouped record, so the sampled output still has one row per original station record.

assess_result · completed · assessment: sufficient

The delivered selected-station artifact contains 530 qualifying records. Inspection shows it retains point geometry plus benchmark_row_id, State and snowfall_in. The selected rows have snowfall_in values from 12.019136428833008 to 372.04315185546875 inches with no nulls, so every delivered row meets the strict greater-than-12-inch rule. The selection was produced from the 50-state eligible station set, which contains 1,003 records filtered by the supplied State attribute before the >12 inch selection was applied.

assess_result · completed · assessment: sufficient

The final state comparison is supported by the delivered selected-station artifact and grouped counts table. There are 530 qualifying US station records with snowfall_in strictly greater than 12 inches and 36 eligible US records with unknown snowfall. Michigan has the highest count with 55, followed by Pennsylvania with 50, New York with 41, Wisconsin with 38, and Oregon with 33. The grouped counts table contains 36 positive states, and the counts sum to the 530 delivered selected records.

Recorded workflow

  1. 01

    Selected Amtrak stations (>12 in snowfall)

    Recorded output · succeeded

  2. 02

    State counts of selected Amtrak stations

    Recorded output · succeeded

  3. 03

    Keep 50 US states

    Recorded vector-filter · succeeded

  4. 04

    Sample snowfall at stations

    Recorded raster-sample · succeeded

  5. 05

    Select stations above 12 inches

    Recorded vector-filter · succeeded

  6. 06

    Frozen snowfall raster

    Recorded source · succeeded

  7. 07

    Count selected stations by state

    Recorded table-group-statistics · succeeded

  8. 08

    Amtrak stations

    Recorded source · succeeded

  9. 09

    Eligible US stations with unknown snowfall

    Recorded vector-filter · skipped

  10. 10

    id counts

    Recorded table-group-statistics · succeeded

  11. 11

    sample all

    Recorded raster-sample · succeeded

  12. 12

    Frozen snowfall raster

    Recorded source · succeeded

  13. 13

    Amtrak stations

    Recorded source · succeeded

  14. 14

    sample all

    Recorded output · succeeded

  15. 15

    id counts

    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 current analysis context, confirm the input schemas, then run a small private test before saving the full workflow.

  2. get_analysis

    Recorded tool call · completed

  3. Progress update

    I found the Blue analysis tools. Next I’m confirming the supplied station fields and snowfall raster details, then I’ll test the point-sampling method on a small private slice before I save the full run.

  4. get_collection

    Recorded tool call · completed

  5. get_collection

    Recorded tool call · completed

  6. list_processors

    Recorded tool call · completed

  7. list_processors

    Recorded tool call · completed

  8. get_tool_help

    Recorded tool call · completed

  9. Progress update

    I’ve confirmed the inputs. The key remaining uncertainty is whether the station file already has one row per benchmark_row_id and whether raster sampling returns a clean snowfall field with null for NoData. I’m testing that privately now on a small slice.

  10. describe_processors

    Recorded tool call · completed

  11. get_tool_help

    Recorded tool call · completed

  12. update_analysis_brief

    Recorded tool call · completed

  13. list_processors

    Recorded tool call · completed

  14. get_tool_help

    Recorded tool call · completed

  15. describe_processors

    Recorded tool call · completed

  16. Progress update

    I have the processor schemas. I’m now running the first private check on the actual inputs: sample snowfall onto the stations, inspect the added field name and null handling, and verify whether benchmark_row_id stays one row per station.

  17. run_trial

    Recorded tool call · completed

  18. Progress update

    The private test answered the method question. Sampling added a `snowfall_in` field, it preserved `benchmark_row_id` and `State`, null stayed unknown, and every `benchmark_row_id` still appears once. I’m turning that tested method into the full workflow now.

  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. get_tool_help

    Recorded tool call · completed

  25. assess_trial

    Recorded tool call · completed

  26. get_tool_help

    Recorded tool call · completed

  27. Progress update

    I’ve turned the tested sampling step into the full method: sample snowfall to stations, keep only the 50 state codes, split selected `>12` from unknown `null`, then group the selected stations by the supplied `State` field. I’m saving that workflow draft and validating it now.

  28. propose_workflow

    Recorded tool call · failed

  29. Progress update

    The draft needed one correction: two requirement bindings pointed at the unknown-snow support branch, which does not feed the saved deliverables. I’m fixing those references now without changing the method.

  30. propose_workflow

    Recorded tool call · completed

  31. Progress update

    The method is now saved and validated. It keeps the user’s rules unchanged: same supplied raster, same station `State` field, strict `>12`, unknown stays unknown, and the final saved outputs are the selected stations and the grouped state counts. I’m running it and then I’ll inspect the delivered artifacts.

  32. execute_workflow

    Recorded tool call · completed

  33. inspect_workflow_results

    Recorded tool call · completed

  34. Progress update

    The run finished in the background. I’m inspecting the saved outputs now so I can report the verified station selection, the state counts, and the remaining unknown coverage.

  35. inspect_artifact

    Recorded tool call · completed

  36. get_tool_help

    Recorded tool call · completed

  37. Progress update

    I’ve got the finished outputs. The remaining checks are mechanical now: read the selected-station fields, read the grouped counts table, and read the null count on the 50-state station set so the final answer object is exact.

  38. inspect_artifact

    Recorded tool call · completed

  39. inspect_artifact

    Recorded tool call · completed

  40. inspect_artifact

    Recorded tool call · completed

  41. Progress update

    The selected-station artifact is verified: 530 rows, original geometry kept, `benchmark_row_id` unique, `State` kept, and `snowfall_in` present with a minimum above 12. I’m reading the grouped counts table now, then I’ll read the unknown count from the eligible 50-state set.

  42. inspect_artifact

    Recorded tool call · failed

  43. Progress update

    I already have the positive selection and the grouped counts. One final lookup remains: the count of eligible 50-state station records where snowfall is unknown, so the delivered answer object matches the run exactly.

  44. inspect_workflow_results

    Recorded tool call · completed

  45. inspect_artifact

    Recorded tool call · completed

  46. Progress update

    I have the selected rows and all positive state counts. I’m pulling the last exact figure now: the null count on the 50-state station set, so the final answer object matches the saved artifacts exactly.

  47. inspect_artifact

    Recorded tool call · completed

  48. get_tool_help

    Recorded tool call · completed

  49. Progress update

    I have the exact unknown count now. The result is complete: 1,003 eligible 50-state station records, 36 unknown snowfall records, and 530 selected records above 12 inches. I’m recording the inspected final outputs and answer object now.

  50. get_analysis

    Recorded tool call · completed

  51. Progress update

    I’ve verified the final outputs. I’m refreshing the brief notes so the saved analysis reflects the delivered result rather than the earlier planning checks.

  52. update_analysis_brief

    Recorded tool call · completed

  53. Progress update

    I updated the saved brief notes after the run, so I’m revalidating the retained workflow record once to keep the saved planning state consistent with the delivered result.

  54. revise_workflow

    Recorded tool call · completed

  55. Progress update

    I’m recording the selected-station result first, then the grouped comparison with the machine-readable answer object.

  56. assess_result

    Recorded tool call · completed

  57. Progress update

    I’m saving the grouped comparison and the answer object now. It will point to the selected-station artifact and include the exact positive groups and unknown count from the inspected outputs.

  58. assess_result

    Recorded tool call · completed

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