ScaffoldBench

RunHaiku 4.5repeat 2

Plan-execute-verify on HTTP 301 vs 308

claude-haiku-4-5-20251001__plan-execute-verify__research-http-redirects__r2

Score

0.854

wrong answer
design ran as designed
Cost
$0.160
+ $0.065 judging
Latency
1m 49s
setup 0.0s, grading 4.7s
Turns
25
Tool calls
19
Subagents
0
Tokens in / out
177k / 13k
126,639 read from cache

Did the design run?

every check held
  • Run completed: heldharness.run-completedThe environment was built, the architecture returned and grading finished, none of them throwing.
  • No API failures: heldharness.apiNo model call failed at the API.
  • Every call ended: heldharness.calls-endedEvery call ended with a result, or was stopped by the run's own limits.
  • No harness tool denied: heldharness.harness-toolsThe sandbox guard never denied a harness tool, nor a tool the session itself offered.
  • Tool servers connected: heldharness.mcp-connectedEvery tool server the harness gave a call was connected when the session started.
  • No foreign tool servers: heldharness.mcp-hermeticNo call loaded a tool server the harness did not give it.
  • Builtin tools: heldharness.builtin-toolsA check recorded with the run.
  • Structured replies arrived: heldharness.structured-outputEvery call that asked for structured output and ran to the end got it.
  • No silent fallbacks: heldharness.not-degradedNo phase fell back on a default (an empty plan, a default winner) instead of its output.
  • Judge answered: heldharness.judgeAt least one grading call returned a usable verdict.
  • The plan was a plan: heldplan-execute-verify.planThe planner’s reply was read through its schema and held at least one step.
  • Every verdict was read: heldplan-execute-verify.verdictsEvery review round ended with a verdict read from the schema reply, not a default.
  • The loop did what its verdicts said: heldplan-execute-verify.loopEvery verdict that called for a revision got one, and nothing was revised without such a verdict.
  • Each call was shown the right tools: heldplan-execute-verify.toolsThe planner was shown no tools, the verifier the read-only ones, and the executor and reviser the full toolset.

Phases

Plan: 0.0s to 16.5s, finished, 0 tool calls, $0.015
Execute: 16.5s to 52.2s, finished, 12 tool calls, $0.065
Verify: 52.2s to 1m 49s, finished, 7 tool calls, $0.080

Drawn from the phase records: timing and cost per call, no tool calls or messages.

PhaseDurationCostTurnsToolsModel
Plan16.5s$0.01530claude-haiku-4-5-20251001
Execute35.7s$0.0651312claude-haiku-4-5-20251001
Verify56.5s$0.08097claude-haiku-4-5-20251001

The call-by-call replay is not published for this run. Traces are large, so the repository keeps 9 of this run set’s 900 and leaves the rest out; the score, phases and final answer on this page come from the committed run record.

Runs you can replay

Record this cell yourself: npm run bench -- run --strategies plan-execute-verify --tasks research-http-redirects --models claude-haiku-4-5-20251001 --repeats 1

Score breakdown

  • passStates that 301 is "Moved Permanently" and 308 is "Permanent Redirect", and that both indicate the target resource has been assigned a new permanent URI.
    1.00weight 0.17

    met, backed by verified evidence E1, E2. “Both HTTP 301 (Moved Permanently) and HTTP 308 (Permanent Redirect) indicate that a resource has been permanently moved to a new URI.”

  • passStates that a client following a 308 must not change the request method: a POST is repeated as a POST, with its body.
    1.00weight 0.25

    met, backed by verified evidence E4. “a POST request must remain a POST request to the new URI, and the request body should be resent with the new request.”

  • passStates that when following a 301 a user agent MAY change the request method from POST to GET (for historical reasons), which is the behaviour 308 exists to rule out.
    1.00weight 0.25

    met, backed by verified evidence E3, E4. “for historical reasons, a user agent may change the request method from POST to GET when following a 301 redirect.”

  • passStates that both 301 and 308 responses are heuristically cacheable, i.e. a cache may reuse them by default unless the method definition or explicit cache controls say otherwise.
    1.00weight 0.17

    met, backed by verified evidence E5, E6. “a 301 response is heuristically cacheable unless otherwise indicated by method definition or explicit cache controls. Similarly, a 308 response is heuristically cacheable under the same conditions.”

  • partialStates that both codes are currently specified in RFC 9110 (HTTP Semantics), and that 308 was originally defined in RFC 7538, which RFC 9110 obsoletes.
    0.13weight 0.17

    partial, but no evidence entry supports it. “Both codes are also reflected in **RFC 9110** (HTTP Semantics), which is the more recent consolidated HTTP specification.”

Penalties

No penalties were applied.

Scorer metadata

corpus
{"version":2,"snapshot":"2026-10-01","hash":"25fbed79c4f7f9e1b850436e0e4872f8e25dd80142f3177231c456f21817b817","documents":8}
opened documents
["rfc7231","rfc7538","rfc9110"]
opened by role
{"superseded":["rfc7231","rfc7538"],"primary":["rfc9110"]}
displayed share
{"rfc7231":0.0653,"mdn-status-301":0.2657,"rfc7538":1,"mdn-status-308":0.1219,"rfc9110":0.0383}
cited count
2
verified count
2
hallucinated count
0
citation integrity
1
hallucinated urls
[]
evidence block
true
evidence block repaired
false
evidence count
8
verified quote count
7
verified quote rate
0.875 (88%)
evidence
[{"url":"https://www.rfc-editor.org/rfc/rfc7231.html","claim":"301 indicates that the target resource has been assigned a new permanent URI","quote":"The 301 (Moved Permanently) status code indicates that the target resource has been assigned a new permanent URI and any future references to this resource ought to use one of the enclosed URIs.","verified":true,"document":"rfc7231"},{"url":"https://www.rfc-editor.org/rfc/rfc7538.html","claim":"308 indicates that the target resource has been assigned a new permanent URI","quote":"The 308 (Permanent Redirect) status code indicates that the target resource has been assigned a new permanent URI and any future references to this resource ought to use one of the enclosed URIs.","verified":true,"document":"rfc7538"},{"url":"https://www.rfc-editor.org/rfc/rfc7231.html","claim":"301 allows user agents to change the request method from POST to GET for historical reasons","quote":"Note: For historical reasons, a user agent MAY change the request method from POST to GET for the subsequent request.","verified":true,"document":"rfc7231"},{"url":"https://www.rfc-editor.org/rfc/rfc7538.html","claim":"308 does not allow changing the request method from POST to GET","quote":"Note: This status code is similar to 301 (Moved Permanently) ([RFC7231], Section 6.4.2), except that it does not allow changing the request method from POST to GET.","verified":true,"document":"rfc7538"},{"url":"https://www.rfc-editor.org/rfc/rfc7231.html","claim":"301 response is cacheable by default","quote":"A 301 response is cacheable by default; i.e., unless otherwise indicated by the method definition or explicit cache controls (see Section 4.2.2 of [RFC7234]).","verified":true,"document":"rfc7231"},{"url":"https://www.rfc-editor.org/rfc/rfc7538.html","claim":"308 response is cacheable by default","quote":"A 308 response is cacheable by default; i.e., unless otherwise indicated by the method definition or explicit cache controls (see [RFC7234], Section 4.2.2).","verified":true,"document":"rfc7538"},{"url":"https://www.rfc-editor.org/rfc/rfc7231.html","claim":"301 is specified in RFC 7231","quote":"6.4.2. 301 Moved Permanently","verified":true,"document":"rfc7231"},{"url":"https://www.rfc-editor.org/rfc/rfc7538.html","claim":"308 is specified in RFC 7538","quote":"3. 308 Permanent Redirect","verified":false,"document":"rfc7538","failure":"the quote has fewer than 6 consecutive words"}]
judge unverified quotes
0
judge verdicts
[{"names":{"status":"met","support":["E1","E2"]},"method-preserved-308":{"status":"met","support":["E4"]},"method-change-301":{"status":"met","support":["E3","E4"]},"cacheable":{"status":"met","support":["E5","E6"]},"specifications":{"status":"partial","support":[]}},{"names":{"status":"met","support":["E1","E2"]},"method-preserved-308":{"status":"met","support":["E4"]},"method-change-301":{"status":"met","support":["E3"]},"cacheable":{"status":"met","support":["E5","E6"]},"specifications":{"status":"partial","support":[]}},{"names":{"status":"met","support":["E1","E2"]},"method-preserved-308":{"status":"met","support":["E4"]},"method-change-301":{"status":"met","support":["E3"]},"cacheable":{"status":"met","support":["E5","E6"]},"specifications":{"status":"partial","support":[]}}]
judge failures
0
grounded weight share
0.8333333333333334 (83%)

Final answer

Perfect! I now have all the information I need to provide a comprehensive answer. Let me compile the findings.

Differences Between HTTP Status Codes 301 and 308

What Each Code Means

Both HTTP 301 (Moved Permanently) and HTTP 308 (Permanent Redirect) indicate that a resource has been permanently moved to a new URI. The 301 status code signifies that the target resource has been assigned a new permanent URI and any future references should use the new URI. Similarly, the 308 status code indicates the same permanent relocation of a resource.

How Clients Handle Request Methods and Bodies

The critical difference between these two status codes lies in how clients should handle the request method when following the redirect:

301 Moved Permanently allows clients to change the request method. Specifically, for historical reasons, a user agent may change the request method from POST to GET when following a 301 redirect. This means if a client made a POST request and receives a 301 response, it may convert the subsequent request to the new URI into a GET request.

308 Permanent Redirect explicitly prohibits this behavior. Unlike 301, the 308 status code does not allow changing the request method from POST to GET. When a client receives a 308 response, it must preserve the original request method for the redirect request. This means a POST request must remain a POST request to the new URI, and the request body should be resent with the new request.

Cacheability

Both status codes are cacheable by default. According to the current HTTP specifications, a 301 response is heuristically cacheable unless otherwise indicated by method definition or explicit cache controls. Similarly, a 308 response is heuristically cacheable under the same conditions. This means both responses can be stored by caches and reused for subsequent requests without requiring revalidation with the origin server.

Current Specifications

The 301 status code is originally specified in RFC 7231 (Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content), Section 6.4.2. RFC 7231 explicitly notes that clients may change the request method from POST to GET for historical reasons, and recommends using 307 (Temporary Redirect) if this behavior is undesired.

The 308 status code is specified in RFC 7538 (The Hypertext Transfer Protocol Status Code 308 (Permanent Redirect)), Section 3. RFC 7538 was created specifically to provide a permanent redirect counterpart to 301 that does not allow method changes. The 308 code explicitly does not allow changing the request method from POST to GET.

Both codes are also reflected in RFC 9110 (HTTP Semantics), which is the more recent consolidated HTTP specification. RFC 9110 updates and maintains the definitions of both 301 and 308, confirming their status as heuristically cacheable codes.

{"evidence": [{"claim": "301 indicates that the target resource has been assigned a new permanent URI", "quote": "The 301 (Moved Permanently) status code indicates that the target resource has been assigned a new permanent URI and any future references to this resource ought to use one of the enclosed URIs.", "url": "https://www.rfc-editor.org/rfc/rfc7231.html"}, {"claim": "308 indicates that the target resource has been assigned a new permanent URI", "quote": "The 308 (Permanent Redirect) status code indicates that the target resource has been assigned a new permanent URI and any future references to this resource ought to use one of the enclosed URIs.", "url": "https://www.rfc-editor.org/rfc/rfc7538.html"}, {"claim": "301 allows user agents to change the request method from POST to GET for historical reasons", "quote": "Note: For historical reasons, a user agent MAY change the request method from POST to GET for the subsequent request.", "url": "https://www.rfc-editor.org/rfc/rfc7231.html"}, {"claim": "308 does not allow changing the request method from POST to GET", "quote": "Note: This status code is similar to 301 (Moved Permanently) ([RFC7231], Section 6.4.2), except that it does not allow changing the request method from POST to GET.", "url": "https://www.rfc-editor.org/rfc/rfc7538.html"}, {"claim": "301 response is cacheable by default", "quote": "A 301 response is cacheable by default; i.e., unless otherwise indicated by the method definition or explicit cache controls (see Section 4.2.2 of [RFC7234]).", "url": "https://www.rfc-editor.org/rfc/rfc7231.html"}, {"claim": "308 response is cacheable by default", "quote": "A 308 response is cacheable by default; i.e., unless otherwise indicated by the method definition or explicit cache controls (see [RFC7234], Section 4.2.2).", "url": "https://www.rfc-editor.org/rfc/rfc7538.html"}, {"claim": "301 is specified in RFC 7231", "quote": "6.4.2. 301 Moved Permanently", "url": "https://www.rfc-editor.org/rfc/rfc7231.html"}, {"claim": "308 is specified in RFC 7538", "quote": "3. 308 Permanent Redirect", "url": "https://www.rfc-editor.org/rfc/rfc7538.html"}]}

Provenance of the numbers on this page

run set
scaffold-or-scale-v1
models
Haiku 4.5, Sonnet 5.5, Opus 5.5
effort
high
repeats
2
fixtures
replay
runs
900 / 900
strategy cost
$354.44
judge cost
$9.19
wall clock
9h 48m
git
fce5807b2d

Cost excludes judge calls, which are tracked separately so a scoring model never flatters or penalises an architecture. Every figure on this site is read from results/ at build time.