reverse-engineering-anything/experiments/atomic-codemode/savepoint-control-study.md

Real-agent savepoint control investigation

The question and oracle were committed at e2205313a before either model launch. Both lanes have the same atomic facts, target, engine, question and common envelope/stopping guidance. They start with the function name and two messages, without supplied code addresses. This tests the newly available full recovered graph, not provider parity or superiority over a traditional RE interface.

Initial pair: natural discovery

Both complete answers pass the frozen source/answer review:

• Incoming string references select 0xea6d0 from two same-name entries before one retained VM capture. Neither lane fetches the complete C report or graph.
• Both format pointers merge through 0xf238b:ceb7 and reach CALL 0xf238b:7130, with the correct predecessor/edge bindings and RSI storage.
• Each answer supplies both successor edges for each nearest local conditional predecessor. The open guard is signed four-byte 0 < loaded32; release is four-byte equality to one. Both trace one-byte Booleans to the right LOADs, preserve operand indexes/widths and stop before guessing loaded contents.
• Focused instruction windows check loads, the spill, signed JG/equality JZ, format setups and shared machine CALL. Independent GNU/ELF verification checks eleven instruction sites against the same target bytes. PHI/edge identities remain separate from machine instructions and transfers.
• Real source IDs and the target digest are present. Each answer limits itself to recovered graph/local guards and states machine-flow, alias, nontermination, earlier-path and runtime-feasibility limits. Neither uses derived controllers or claims a SQL trigger. Both close the lease.

Each answer cites ten observed source IDs. Both have one successful VM capture, whose recovered graph equals the complete producer golden; facts come from the preserved 677b9795... engine. Full answers, events, tool context, traces and resource receipts are retained locally under .cache/atomic-codemode/sqlite-savepoint-control-{direct,codemode}-v1*.

Whole-task measure	Direct atomic	Code Mode
Cumulative input tokens	515,024	610,715
Included cached input	466,304	563,328
Uncached input	48,720	47,387
Output tokens	5,537	6,345
Included reasoning output	1,344	1,502
Observed model responses	17	18
MCP attempts, including rejection	24	15
Successful atomic fact reads	20	21
Model wall seconds	206.269	223.636
Family wall seconds	207.427	224.133
Family CPU seconds	53.794	52.777
Kernel process-family peak MiB	874.9	883.2

Code Mode's fifteen attempts include a rejected timeout_ms:200000 request; the actual schema maximum is 120,000. It retries within that bound. The client also initially tries to JSON-parse the validation error's text and gets a SyntaxError. Both costs remain in the ledger. There are no recorded inner-API failures or resource aborts. Direct has no failed MCP attempt. MCP attempts, successful host reads, client execution calls and model responses are distinct counts; the trace has no handler entry for the schema rejection.

In this one sample, Code Mode reduces uncached input by about 2.7% but increases cumulative input by 18.6%, output by 14.6% and model wall time by 8.4%. Fewer MCP requests do not establish a whole-task advantage. The lanes also choose slightly different fact selections and output detail. This is an observational pair, not a controlled estimate of a single dispatch mechanism's causal effect.

The first client discovery call in both lanes applies a broad rea.*... regular expression to all tool names/descriptions. It matches unrelated tools, including creation tools, and prints large, truncated metadata. This is a real observed agent cost, not an analysis-provider failure; it also adds noise to comparing the two interfaces. A repeat should give both lanes the same exact-name discovery policy while retaining every advertised tool and charging that guidance to the whole task. No analysis steps, addresses or answers should be added.

Both runs request gpt-6.1-sol/high through Codex 0.161.0; the resolved service build is unknown. Per-response usage sums match the runner ledger. Cached input is already included in input, and reasoning is included in output. One CPU, 4 GiB hard / 3 GiB early-stop limits apply. Kernel peak includes charged file cache; it is not RSS. Both runs have OOM 0, verified payload/profile cleanup, unchanged runtime fingerprints, engine and target digests. Each lease is fresh; OS/provider-service caches and remote compute costs are uncontrolled/unmeasured.

Discovery-controlled repeat

Pending. The intended repeat keeps the same question, oracle, native engine and all atomic methods, reverses lane order, and uses the runner's existing --enabled-tools / --guide-enabled-tools options with server name rea. Each manifest lists that lane's complete catalog, so no analysis tool is removed. This changes discovery guidance and namespace together for both lanes; it is a separate stratum from the natural-discovery pair, not a retroactive replacement.