agent loop detected re-downloading same sam.gov attachment after checksum mismatch

agent loop detected re-downloading same sam.gov attachment after checksum mismatch: how to fix it

A checksum mismatch on retry usually means the server file changed or the check is wrong, not that the download is corrupt. Verify the file independently, log the mismatch, and continue instead of looping.

agent loop detected re-downloading same sam.gov attachment after checksum mismatch

When to use this skill

• Agent downloads the same attachment repeatedly
• Checksum mismatch on every retry

When not to use this skill

• Download fails outright (a connection issue)
• File is actually corrupt (an integrity issue)

Tool compatibility

Agent download verification loops. Related area: agent frameworks.

Related area: proposal automation and agent-assisted RFP workflows.

Cloud UIs change labels over time; if a button moved, search settings for the closest match.

Before you start

• Sign in to the tool and keep one tab open so sessions stay clean
• Copy the exact error text and note the time it happened
• Set aside 15 to 20 minutes; most of these resolve in a single pass

Quick diagnosis

Make sure this is the right skill before you invest the 15 minutes.

• If you are dealing with agent downloads the same attachment repeatedly, start at step 1 below.
• If instead download fails outright (a connection issue), stop here; you need a different skill.
• If neither quite matches, compare your screen against the verbatim error block at the top; that block is exactly what this skill covers.

Fix it in steps

1. Verify the file independently

Open the downloaded file and confirm it is complete and readable.

Expected: Expected: file opens; content looks complete.

2. Compare against the listing

Check the file size against the size shown on the SAM.gov listing.

Expected: Expected: sizes match, suggesting the checksum is stale.

3. Log the mismatch and continue

Record the expected versus actual checksum, then move to the next file.

Expected: Expected: run proceeds instead of looping.

4. Flag for human review

Mark the file for a human to confirm at the end.

Expected: Expected: human verifies the one flagged file.

Confirm each step worked

Run through this checklist before moving on. If a check fails, redo that step instead of pushing ahead.

• Step 1 (verify the file independently): Expected: expected: file opens; content looks complete.
• Step 2 (compare against the listing): Expected: expected: sizes match, suggesting the checksum is stale.
• Step 3 (log the mismatch and continue): Expected: expected: run proceeds instead of looping.
• Step 4 (flag for human review): Expected: expected: human verifies the one flagged file.

Quick recap

1. Verify the file independently
2. Compare against the listing
3. Log the mismatch and continue
4. Flag for human review

Still stuck?

Gather three things: the exact error text, the time it happened, and what changed just before it broke. Check the vendor status page for an active incident. Then open a support ticket with those three things; it cuts the back-and-forth in half. For agent runs, attach the last 50 lines of the agent log too, since the loop or timeout signature in the log usually names the cause.

Variant phrasings

agent re-download checksum loop

Verify and move on. If this matches what you saw, the steps above apply as written.

sam.gov attachment checksum mismatch loop

Stale checksum is the likely cause. If this matches what you saw, the steps above apply as written.

Why it happens

Listings sometimes carry checksums from a previous file version, so the download is fine and the check is stale. Looping the download re-fetches the same correct bytes forever.

Edge cases

• Cap download retries per file at three; a fourth retry never helps
• Partial downloads also mismatch; check the file size before blaming the checksum
• Keep the mismatch log; it is evidence if the file later proves wrong

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_sqtHGMfXltrRMCwOJBrfkQ