conditional GET returned 200 with identical bytes — diagnosis

Agent diagnostic brief

Exact symptom

conditional GET returned 200 with identical bytes

Where it has been observed

Cloudflare Workers; compressed conditional GET.

Likely distinct causes

The representation changed between requests.
The edge's weak validator was semantically equivalent but rejected by strict string comparison.

How to distinguish them

Equivalent weak or strong tags in If-None-Match, list members, and wildcard produce the RFC-defined conditional result without changing stored state.
Check red test against the same bounded execution window.
Check identity-encoding control against the same bounded execution window.
Check corrected test against the same bounded execution window.
Check 310-request production canary against the same bounded execution window.
Check before and after database hashes against the same bounded execution window.

Current approaches

Apply RFC weak entity-tag comparison to If-None-Match validators (solution-http-if-none-match-weak-etag, revision 1).

Known obsolete approaches

Do not copy a historical workaround across versions without checking current product behavior.
Do not bypass permissions, security controls, or ownership boundaries merely to suppress the symptom.

Versions and freshness

Observed 2026-09-10; RFC 9110 current semantics rechecked 2026-09-11
Editorial and primary-source review date: 2026-09-11.

What remains unknown

Behavior outside the stated products, versions, and environments remains unknown.
Independent reproduction by a different operator has not been established.

Deeper evidence

Problem

If-None-Match returns 200 for an equivalent weak ETag

Observed symptom

An origin implementation compared entity tags strictly, so a weak tag produced by edge compression did not match and an unchanged conditional GET returned 200 instead of 304.
The historical observation is same-operator evidence and does not establish general prevalence.

Operator goal

Complete conditional GET after edge compression without mistaking process success for product acceptance.

Current understanding

An origin implementation compared entity tags strictly, so a weak tag produced by edge compression did not match and an unchanged conditional GET returned 200 instead of 304.
Current primary material was reviewed on 2026-09-11; historical behavior remains bounded to Observed 2026-09-10; RFC 9110 current semantics rechecked 2026-09-11.

Known limitations

The observed result applies to one sanitized same-operator execution and the stated version boundary, not every environment.
Recheck product documentation and preserve the variable changed before generalizing the diagnosis.

Known negative results

Accept only an exact strong entity-tag string. Result: Failed to implement If-None-Match weak comparison and ignored validator lists and wildcard.
No same-operator execution in this release counts as an independent reproduction.

Primary and recurrence sources

Cloudflare cache response documentation
Primary · Primary documentation · Date not supplied · Reviewed 2026-09-11 · Rights: allowed_to_summarize
Current primary material reviewed for Historical Corpus 1: Cloudflare cache response documentation.
RFC 9110 If-None-Match
Primary · Primary specification · Date not supplied · Reviewed 2026-09-11 · Rights: allowed_to_summarize
Current primary material reviewed for Historical Corpus 1: RFC 9110 If-None-Match.

Rights and provenance

Origin

Based on a real operator execution; identifying project details removed.

Rights

State: allowed_to_summarize
Review basis: Owner-authorized factual synthesis of the operator's own execution, independently written from reviewed current primary sources; no transcript expression is published.

Editorial review date

2026-09-11

Known approaches

solution · Revision 1

Apply RFC weak entity-tag comparison to If-None-Match validators

Production corpus importer · 2026-09-11T10:30:00.000Z
Operator Knowledge for Agents editorial · Historical operator record · Digital source: trainedAlgorithmicMedia · Rights: owned

## Candidate action - Apply RFC weak entity-tag comparison to If-None-Match validators. Start by capturing the exact failed stage, current product version, and a bounded before-state. Apply only the smallest evidence-backed change, then repeat the original operation and verify its output independently. This is a candidate procedure supported by one same-operator execution, not a universal fix. ## Applicability - Use when the observed signature is: conditional GET returned 200 with identical bytes. - Observed scope: Cloudflare Workers; compressed conditional GET. - Stop if the first failed stage or product boundary differs. ## Procedure - Equivalent weak or strong tags in If-None-Match, list members, and wildcard produce the RFC-defined conditional result without changing stored state. - Repeat the request with identity encoding and compare status, bytes, and database snapshots. Verify: Identity encoding returned 304 while compressed delivery returned 200 with identical bytes; product state stayed unchanged. - Implement weak comparison for list members and wildcard, then repeat the full canary. Verify: Conditional requests returned 304 and the corrected canary passed. - Compare the post-change result with the captured before-state and preserve exact readback evidence. ## Limitations - One same-operator execution does not establish cross-operator support. - The procedure does not establish behavior for unreviewed versions, environments, or concurrent state changes. ## Obsolete approaches - Do not reuse a version-specific command or workaround without current documentation review. - Do not infer product completion from a lower-layer command exit alone. ## Negative results - Accept only an exact strong entity-tag string. Result: Failed to implement If-None-Match weak comparison and ignored validator lists and wildcard. - No external or same-operator report was promoted to independent reproduction credit. ## Evidence boundary - Grounded in current primary source records src-rfc9110-if-none-match, src-cloudflare-cache-responses-current. - Historical Grade A observation date: 2026-09-10; identifying details removed. - Only immutable manifest executions count as Knowledge for Agents Attempts or Outcomes. ## What remains unknown - Whether the same approach works outside the stated environment remains unknown. - Independent reproduction and universal applicability are not established.

Applicability

State

partial

Text

Applies only when the failed stage matches conditional GET returned 200 with identical bytes.

Facts

Component: If-None-Match validator
Operation: conditional GET after edge compression
Protocol: HTTP

Historical date

2026-09-10

Verification grade

Operator relationship

same_operator

Independent reproduction

false

Provenance disclosure

Based on a real operator execution; identifying project details removed.

Pack

Candidate action: Apply RFC weak entity-tag comparison to If-None-Match validators. Start by capturing the exact failed stage, current product version, and a bounded before-state. Apply only the smallest evidence-backed change, then repeat the original operation and verify its output independently. This is a candidate procedure supported by one same-operator execution, not a universal fix.
Applicability: Use when the observed signature is: conditional GET returned 200 with identical bytes.
Observed scope: Cloudflare Workers; compressed conditional GET.
Stop if the first failed stage or product boundary differs.
Steps: Equivalent weak or strong tags in If-None-Match, list members, and wildcard produce the RFC-defined conditional result without changing stored state.
Repeat the request with identity encoding and compare status, bytes, and database snapshots. Verify: Identity encoding returned 304 while compressed delivery returned 200 with identical bytes; product state stayed unchanged.
Implement weak comparison for list members and wildcard, then repeat the full canary. Verify: Conditional requests returned 304 and the corrected canary passed.
Compare the post-change result with the captured before-state and preserve exact readback evidence.
Limitations: One same-operator execution does not establish cross-operator support.
The procedure does not establish behavior for unreviewed versions, environments, or concurrent state changes.
Obsolete approaches: Do not reuse a version-specific command or workaround without current documentation review.
Do not infer product completion from a lower-layer command exit alone.
Negative results: Accept only an exact strong entity-tag string. Result: Failed to implement If-None-Match weak comparison and ignored validator lists and wildcard.
No external or same-operator report was promoted to independent reproduction credit.
Evidence boundary: Grounded in current primary source records src-rfc9110-if-none-match, src-cloudflare-cache-responses-current.
Historical Grade A observation date: 2026-09-10; identifying details removed.
Only immutable manifest executions count as Knowledge for Agents Attempts or Outcomes.
What remains unknown: Whether the same approach works outside the stated environment remains unknown.
Independent reproduction and universal applicability are not established.

Rights

State: allowed_to_summarize
Review basis: Original diagnostic procedure synthesized from owner-authorized execution facts and linked current primary sources; no private source code, logs, or transcript expression is published.

Source ids

src-rfc9110-if-none-match
src-cloudflare-cache-responses-current