diff --git a/docs/cli.md b/docs/cli.md
index 3c743cd68a..d7414f514e 100644
--- a/docs/cli.md
+++ b/docs/cli.md
@@ -744,10 +744,12 @@ not read artifact contents: the inventories of two builds are unresolved
 records, or one opaque change when you pair them. Use `compare-artifacts`,
 described at the end of this section, to compare their contents.
 
-`--record_pairs` supplies an explicit JSON array of observation pairs, matching
-MCP `compare_bundles.record_pairs`. Pair IDs must exist on their named sides and
-be one-to-one. Without pairs, one-sided membership remains unknown; REA does
-not infer correspondence from position or display names.
+`--record_pairs` accepts an inline JSON array or the path to a local JSON
+file containing that array, matching MCP `compare_bundles.record_pairs`. For a
+file, use `rea compare left.json right.json --record_pairs pairs.json --json`.
+Pair IDs must exist on their named sides and be one-to-one. Without pairs,
+one-sided membership remains unknown; REA does not infer correspondence from
+position or display names.
 
 Exports preserve an existing destination unless `--overwrite` is explicit.
 
diff --git a/src/cliEvidenceCommands.ts b/src/cliEvidenceCommands.ts
index 1442ddd5ed..93ead9c8e5 100644
--- a/src/cliEvidenceCommands.ts
+++ b/src/cliEvidenceCommands.ts
@@ -1,6 +1,5 @@
 import { withCommandCancellation } from "./cli/commandCancellation.js";
-import { safeParseJson } from "./domain/safeJson.js";
-import { AnalysisInputError } from "./domain/analysisErrorCore.js";
+import { parseCliJsonInput } from "./cliJsonInput.js";
 import { analysisInputErrorFromIssues } from "./domain/inputIssueProjection.js";
 import { bundleComparisonInputSchema } from "./domain/bundleComparison.js";
 import { Cli, z } from "incur";
@@ -72,7 +71,7 @@ export const registerEvidenceCommands = (
         .string()
         .optional()
         .describe(
-          "JSON array of explicit left_evidence_id/right_evidence_id observation pairs",
+          "Inline JSON array or local JSON file of left_evidence_id/right_evidence_id pairs",
         ),
     }),
     run: ({ args, options }) =>
@@ -81,21 +80,12 @@ export const registerEvidenceCommands = (
           const decoded =
             options.record_pairs === undefined
               ? { ok: true as const, value: [] }
-              : safeParseJson(options.record_pairs);
-          if (!decoded.ok)
-            return cliError(
-              new AnalysisInputError(
-                "compare_bundles",
-                { cause: decoded.cause },
-                [
-                  {
-                    path: ["record_pairs"],
-                    reason: "invalid_format",
-                    expected: "JSON array",
-                  },
-                ],
-              ),
-            );
+              : await parseCliJsonInput(
+                  options.record_pairs,
+                  "compare_bundles",
+                  signal,
+                );
+          if (!decoded.ok) return decoded.error;
           const input = { record_pairs: decoded.value };
           const selected = bundleComparisonInputSchema
             .pick({ record_pairs: true })
diff --git a/tests/boundary/cli/bundleComparisonCli.test.ts b/tests/boundary/cli/bundleComparisonCli.test.ts
index fcf164b79b..d09f466eff 100644
--- a/tests/boundary/cli/bundleComparisonCli.test.ts
+++ b/tests/boundary/cli/bundleComparisonCli.test.ts
@@ -123,16 +123,10 @@ cliTest(
         right_evidence_id: different.records[0]!.evidence_id,
       },
     ];
-    const paired = await cli.run({
-      arguments: [
-        "compare",
-        leftPath,
-        changedPath,
-        "--record_pairs",
-        JSON.stringify(pairs),
-        "--json",
-      ],
-    });
+    const pairArgs = ["compare", leftPath, changedPath, "--record_pairs"];
+    const compareWithPairs = (value: string) =>
+      cli.run({ arguments: [...pairArgs, value, "--json"] });
+    const paired = await compareWithPairs(JSON.stringify(pairs));
     expect(paired.exitCode).toBe(0);
     const pairedResult = bundleComparisonResultSchema.parse(paired.json);
     expect(pairedResult).toMatchObject({
@@ -142,6 +136,21 @@ cliTest(
         { classification: "changed", conclusion_kind: "observed_change" },
       ],
     });
+    const pairFile = join(root, "pairs.json");
+    await writeFile(pairFile, JSON.stringify(pairs));
+    const fromFile = await compareWithPairs(pairFile);
+    expect(fromFile.exitCode).toBe(0);
+    expect(bundleComparisonResultSchema.parse(fromFile.json)).toEqual(
+      pairedResult,
+    );
+    const missingFile = join(root, "missing-pairs.json");
+    const absentFile = await compareWithPairs(missingFile);
+    expect(absentFile.exitCode).toBe(1);
+    expect(absentFile.json).toMatchObject({
+      code: "invalid_request",
+      input_path: missingFile,
+      input_reason: "read-failed",
+    });
     const call = await cli.sharedMcpCall?.();
     if (call === undefined) throw new Error("Expected shared MCP session");
     const mcp = await call("compare_bundles", {
@@ -155,18 +164,11 @@ cliTest(
         parseEvidence(mcp.structuredContent).normalized_result,
       ),
     ).toEqual(pairedResult);
-    const absentPair = await cli.run({
-      arguments: [
-        "compare",
-        leftPath,
-        changedPath,
-        "--record_pairs",
-        JSON.stringify([
-          { ...pairs[0], left_evidence_id: `ev_${"f".repeat(64)}` },
-        ]),
-        "--json",
-      ],
-    });
+    const absentPair = await compareWithPairs(
+      JSON.stringify([
+        { ...pairs[0], left_evidence_id: `ev_${"f".repeat(64)}` },
+      ]),
+    );
     expect(absentPair.exitCode).toBe(1);
     expect(absentPair.json).toMatchObject({
       code: "invalid_request",