ScaffoldBench

RunOpus 5.5repeat 1

Plan-execute-verify on Twelve HTTP status codes, by the book

claude-opus-5-5__plan-execute-verify__research-status-codes__r1

Score

1.000

passed
design ran as designed
Cost
$0.561
Latency
1m 47s
setup 0.0s, grading 0.3s
Turns
35
Tool calls
30
Subagents
0
Tokens in / out
221k / 10k
174,762 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.
  • 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 19.1s, finished, 0 tool calls, $0.042
Execute: 19.1s to 1m 8s, finished, 11 tool calls, $0.290
Verify: 1m 8s to 1m 47s, finished, 19 tool calls, $0.229

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

PhaseDurationCostTurnsToolsModel
Plan19.1s$0.04220claude-opus-5-5
Execute48.5s$0.2901211claude-opus-5-5
Verify39.7s$0.2292119claude-opus-5-5

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-status-codes --models claude-opus-5-5 --repeats 1

Score breakdown

  • passstatus code 203
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 206
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 303
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 307
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 308
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 405
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 410
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 413
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 414
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 421
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 422
    1.00weight 0.08

    quote verified in rfc9110

  • passstatus code 501
    1.00weight 0.08

    quote verified in rfc9110

Penalties

No penalties were applied.

Scorer metadata

corpus
{"version":2,"snapshot":"2026-10-01","hash":"9841e181cc36236e3bc98c18c73e938cf003a35611d0f06c8d8da6ee7161ee1f","documents":6}
opened documents
["rfc9110","rfc7231"]
opened by role
{"primary":["rfc9110"],"superseded":["rfc7231"]}
displayed share
{"rfc9110":0.1033,"rfc7231":0.0048,"mdn-status-codes":0.0353,"mdn-status-308":0.1405,"rfc9111":0.006,"mdn-status-307":0.1139}
cited count
2
verified count
2
hallucinated count
0
citation integrity
1
hallucinated urls
[]
answer block
true
answer block repaired
false
items answered
12
item count
12
field accuracy
1
grounded items
12
field misses
{}

Final answer

I took all twelve entries from RFC 9110, HTTP Semantics (June 2022), at https://www.rfc-editor.org/rfc/rfc9110.html. A search turned up nothing newer that replaces it, but I didn't check its status page for an "obsoleted by" notice.

How I decided cacheability. Section 15.1 says: "Responses with status codes that are defined as heuristically cacheable (e.g., 200, 203, 204, 206, 300, 301, 308, 404, 405, 410, 414, and 501 in this specification) can be reused by a cache with heuristic expiration unless otherwise indicated by the method definition or explicit cache controls [CACHING]; all other status codes are not heuristically cacheable." (https://www.rfc-editor.org/rfc/rfc9110.html). The sections for each code agree with that list:

  • Cacheable: the sections for 203, 206, 308, 405, 410, 414 and 501 each say "A/The NNN response is heuristically cacheable."
  • Not cacheable: the sections for 303, 307, 413, 421 and 422 have no such sentence.
  • One small difference: for 206, the section's exception mentions only "explicit cache controls." The other codes also mention "the method definition."

Name changes:

  • RFC 9110 calls 413 "Content Too Large." The older RFC 7231 called it "413 Payload Too Large" (https://www.rfc-editor.org/rfc/rfc7231.html), and that name doesn't appear anywhere in RFC 9110.
  • RFC 9110 calls 422 "Unprocessable Content." The plan said it used to be "Unprocessable Entity." That phrase isn't in RFC 9110, and I didn't open the earlier spec that defined it, so I can't confirm the old name.

Quotes. All quotes come from each code's own subsection, not from the 15.1 overview. On the page the sentences are wrapped across several lines with indentation. I joined each one into a single line with normal single spaces.

{"answers":[
{"code":"203","reason":"Non-Authoritative Information","section":"15.3.4","heuristicallyCacheable":true,"quote":"This status code allows the proxy to notify recipients when a transformation has been applied, since that knowledge might impact later decisions regarding the content.","url":"https://www.rfc-editor.org/rfc/rfc9110.html"},
{"code":"206","reason":"Partial Content","section":"15.3.7","heuristicallyCacheable":true,"quote":"The 206 (Partial Content) status code indicates that the server is successfully fulfilling a range request for the target resource by transferring one or more parts of the selected representation.","url":"https://www.rfc-editor.org/rfc/rfc9110.html"},
{"code":"303","reason":"See Other","section":"15.4.4","heuristicallyCacheable":false,"quote":"This status code is applicable to any HTTP method.","url":"https://www.rfc-editor.org/rfc/rfc9110.html"},
{"code":"307","reason":"Temporary Redirect","section":"15.4.8","heuristicallyCacheable":false,"quote":"Since the redirection can change over time, the client ought to continue using the original target URI for future requests.","url":"https://www.rfc-editor.org/rfc/rfc9110.html"},
{"code":"308","reason":"Permanent Redirect","section":"15.4.9","heuristicallyCacheable":true,"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/rfc9110.html"},
{"code":"405","reason":"Method Not Allowed","section":"15.5.6","heuristicallyCacheable":true,"quote":"The 405 (Method Not Allowed) status code indicates that the method received in the request-line is known by the origin server but not supported by the target resource.","url":"https://www.rfc-editor.org/rfc/rfc9110.html"},
{"code":"410","reason":"Gone","section":"15.5.11","heuristicallyCacheable":true,"quote":"The 410 (Gone) status code indicates that access to the target resource is no longer available at the origin server and that this condition is likely to be permanent.","url":"https://www.rfc-editor.org/rfc/rfc9110.html"},
{"code":"413","reason":"Content Too Large","section":"15.5.14","heuristicallyCacheable":false,"quote":"The 413 (Content Too Large) status code indicates that the server is refusing to process a request because the request content is larger than the server is willing or able to process.","url":"https://www.rfc-editor.org/rfc/rfc9110.html"},
{"code":"414","reason":"URI Too Long","section":"15.5.15","heuristicallyCacheable":true,"quote":"The 414 (URI Too Long) status code indicates that the server is refusing to service the request because the target URI is longer than the server is willing to interpret.","url":"https://www.rfc-editor.org/rfc/rfc9110.html"},
{"code":"421","reason":"Misdirected Request","section":"15.5.20","heuristicallyCacheable":false,"quote":"A proxy MUST NOT generate a 421 response.","url":"https://www.rfc-editor.org/rfc/rfc9110.html"},
{"code":"422","reason":"Unprocessable Content","section":"15.5.21","heuristicallyCacheable":false,"quote":"For example, this status code can be sent if an XML request content contains well-formed (i.e., syntactically correct), but semantically erroneous XML instructions.","url":"https://www.rfc-editor.org/rfc/rfc9110.html"},
{"code":"501","reason":"Not Implemented","section":"15.6.2","heuristicallyCacheable":true,"quote":"This is the appropriate response when the server does not recognize the request method and is not capable of supporting it for any resource.","url":"https://www.rfc-editor.org/rfc/rfc9110.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.