{
  "rows": [
    {
      "id": "tool-vdso",
      "concept": "Tool vDSO (3-tier local fast path)",
      "category": "performance",
      "surface": "subsystem",
      "what_you_get": "A read-only/idempotent tool call can be served from a content-addressed local cache instead of re-executing, with automatic invalidation when the world changes.",
      "audience": "developer",
      "maturity": "shipped",
      "claims_section": "Tool vDSO",
      "claims_tag": "SHIPPED",
      "first_command": "",
      "first_command_verb": "",
      "needs_gpu": false,
      "needs_key": false,
      "witness_path": "internal/vdso",
      "witness": "internal/vdso tests (canonicalization, world-version invalidation)",
      "entry_doc": "docs/cli-reference.md",
      "verdict": "real-not-easy",
      "gaps": [
        "Measured real-world hit-rate on tau2-airline is ~0.7% — far below a useful threshold, so the vDSO is an UPSIDE secondary, never the headline (the hit-rate is SIMULATED in the demo)",
        "No standalone surface a person runs; it is a mechanism inside the syscall path"
      ],
      "durability_note": "The 3-tier mechanism is deterministic and unit-proven; a cache hit equals a fresh call by construction (a write bumps the world-version)."
    },
    {
      "id": "syscall-latency-check",
      "concept": "Syscall adjudication latency sentinel (fak bench)",
      "category": "performance",
      "surface": "benchmark",
      "what_you_get": "Run a frozen trace through the binary and watch in-process adjudication (~µs) vs a spawned-hook baseline (~ms) — a regression sentinel that the decide path never pays a per-call process boundary.",
      "audience": "platform",
      "maturity": "shipped",
      "claims_section": "The syscall subsystem latency check",
      "claims_tag": "SHIPPED",
      "first_command": "go run ./cmd/fak bench --suite tau2-smoke",
      "first_command_verb": "bench",
      "needs_gpu": false,
      "needs_key": false,
      "witness_path": "cmd/fak",
      "witness": "report.json gate_primary=='pass'; ~2.4 us in-process vs ~6.9 ms spawned (n=100)",
      "entry_doc": "docs/cli-reference.md",
      "verdict": "usable-today",
      "gaps": [
        "Deliberately NOT a production-readiness, model-quality, or serving-throughput headline — a subsystem regression sentinel only",
        "The ratio is platform-specific (the spawn baseline is this machine)"
      ],
      "durability_note": "The gate is mechanical (in-process < spawn by construction); the vDSO hit-rate can never turn it red."
    },
    {
      "id": "turn-tax-benchmark",
      "concept": "Turn-tax benchmark (the round-trip that never fires)",
      "category": "performance",
      "surface": "benchmark",
      "what_you_get": "Replay a real tool-call trace and count the extra error-recovery model round-trips a naive/tuned loop is forced into that the kernel resolves in the same syscall — with the safety floor on a separate axis.",
      "audience": "researcher",
      "maturity": "shipped",
      "claims_section": "Turn-tax benchmark",
      "claims_tag": "SHIPPED",
      "first_command": "go run ./cmd/turntaxdemo -print",
      "first_command_verb": "turntaxdemo",
      "needs_gpu": false,
      "needs_key": false,
      "witness_path": "internal/turnbench",
      "witness": "internal/turnbench tests incl. TestRun_HappyPathSavesNothing (anti-inflation control)",
      "entry_doc": "docs/cli-reference.md",
      "verdict": "usable-today",
      "gaps": [
        "The replayed trace is a cache-favorable slice; do not extrapolate the extra-turn count as a general agent speedup",
        "The baseline turn cost is modeled; the fak side is live kernel counters"
      ],
      "durability_note": "The fak side is live kernel events (k.Syscall counters), not modeled; a clean control saves exactly 0 (anti-inflation guard)."
    },
    {
      "id": "fanout-benchmark",
      "concept": "Fan-out benchmark (fanbench, N=1..1024 sub-agents)",
      "category": "performance",
      "surface": "benchmark",
      "what_you_get": "Sweep one master goal into N sub-agents and measure the cross-agent tool-result dedup and shared-prefix KV reuse the fan-out buys — the regime no public multi-agent benchmark maps (they top out at 5-7).",
      "audience": "researcher",
      "maturity": "shipped",
      "claims_section": "Fan-out benchmark",
      "claims_tag": "SHIPPED",
      "first_command": "go run ./cmd/fanbench -profile research",
      "first_command_verb": "fanbench",
      "needs_gpu": false,
      "needs_key": false,
      "witness_path": "cmd/fanbench",
      "witness": "TestFanoutNoShareZeroUplift, TestFanoutSingleAgentNoUplift, TestPrefixReuseFanoutWitness",
      "entry_doc": "docs/benchmarks/FANOUT-BENCH-RESULTS.md",
      "verdict": "usable-today",
      "gaps": [
        "The token-multiplier / tax-clawed-back values are a transparent SIMULATED cost model, reported apart from the measured dedup halves",
        "N=1 is a net loss; the win is vs a stack that re-sends the prefix per sub-agent, NOT vs a tuned shared-prefix engine"
      ],
      "durability_note": "The measured cross-agent dedup is a real shared-vs-isolated path swap; the (N-1)*prefix geometry is exact, proven bit-identical."
    },
    {
      "id": "longctx-bench",
      "concept": "Ultra-long-context work floor (longctxbench, >100k tokens)",
      "category": "performance",
      "surface": "benchmark",
      "what_you_get": "Compute the exact, contention-free reread-elimination work floor for the >100k-token regime as closed-form arithmetic from the session shape — no GPU, no live model required.",
      "audience": "researcher",
      "maturity": "shipped",
      "claims_section": "Ultra-long-context work floor",
      "claims_tag": "SHIPPED",
      "first_command": "go run ./cmd/longctxbench -ladder",
      "first_command_verb": "longctxbench",
      "needs_gpu": false,
      "needs_key": false,
      "witness_path": "internal/turnbench",
      "witness": "TestLongContextTokenFloorMatchesSessionbench, TestLongContextAntiInflation, TestPrefillWorkQuadraticDominates",
      "entry_doc": "docs/cli-reference.md",
      "verdict": "usable-today",
      "gaps": [
        "The absolute WALL-CLOCK validation at >100k is SIMULATED (intractable on CPU; awaits a resident-GPU bench node, #524) — only the arithmetic floor is shipped",
        "Decode-batching bandwidth win is excluded to isolate reread-only"
      ],
      "durability_note": "The token floor is byte-identical to sessionbench's prefillTokens (cross-validation); the FLOP floor counts the prefill quadratic exactly — both deterministic and model-independent."
    },
    {
      "id": "prefill-kv-reuse",
      "concept": "Shared-prefix KV reuse (prefill once, clone bit-identically)",
      "category": "performance",
      "surface": "subsystem",
      "what_you_get": "The kernel prefills a shared prompt prefix once and clones the KV bit-identically into every agent, so a read-heavy fleet does the shared setup work one time, not per agent per turn.",
      "audience": "researcher",
      "maturity": "shipped",
      "claims_section": "Fan-out benchmark",
      "claims_tag": "SHIPPED",
      "first_command": "",
      "first_command_verb": "",
      "needs_gpu": false,
      "needs_key": false,
      "witness_path": "internal/model",
      "witness": "TestPrefixReuseFanoutWitness, NewBatchFromPrefix clones bit-identical to an independent full prefill",
      "entry_doc": "docs/benchmarks/FANOUT-BENCH-RESULTS.md",
      "verdict": "real-not-easy",
      "gaps": [
        "The fleet-scale benefit depends on read-heavy shared-context workloads; a ~1% write rate can flip it net-negative",
        "Cross-engine KV share (vLLM/SGLang) is a seam, not shipped"
      ],
      "durability_note": "The bit-identical clone is tested against a reference full-prefill; the (N-1)*prefix geometry is exact, model-independent arithmetic."
    },
    {
      "id": "engine-openai-client",
      "concept": "OpenAI-compatible engine client (record/replay + mock)",
      "category": "performance",
      "surface": "subsystem",
      "what_you_get": "A base-url-swappable OpenAI-compatible client with bounded timeout/backoff, cassette record/replay for deterministic offline runs, and a deterministic mock engine.",
      "audience": "developer",
      "maturity": "shipped",
      "claims_section": "Engine",
      "claims_tag": "SHIPPED",
      "first_command": "",
      "first_command_verb": "",
      "needs_gpu": false,
      "needs_key": false,
      "witness_path": "internal/engine",
      "witness": "engine tests (units 39-45); deterministic mock + cassette replay",
      "entry_doc": "docs/cli-reference.md",
      "verdict": "real-not-easy",
      "gaps": [
        "metrics-service scrape / KV-residency / token-per-watt are SIMULATED telemetry (no watt source on the box)",
        "A library the gateway/agent consume, not a standalone surface"
      ],
      "durability_note": "Cassette replay makes offline runs deterministic and CI-stable; a live run carries a real transcript hash XOR an explicit unverified flag."
    },
    {
      "id": "self-ablation-sweep",
      "concept": "Self-ablation sweep (fak ablate)",
      "category": "performance",
      "surface": "benchmark",
      "what_you_get": "Run `fak ablate --sweep vdso` to replay one frozen tool-call trace under an N-arm feature sweep and print one row per arm with the kernel counters and a per-arm delta vs the baseline — the deterministic, $0, no-model core of the self-ablation harness.",
      "audience": "researcher",
      "maturity": "shipped",
      "claims_section": "Self-ablation sweep (`fak ablate`)",
      "claims_tag": "SHIPPED",
      "first_command": "go run ./cmd/fak ablate --sweep vdso",
      "first_command_verb": "ablate",
      "needs_gpu": false,
      "needs_key": false,
      "witness_path": "internal/ablate",
      "witness": "TestSweep_VDSO_NArmGuardAndIsolatedDelta, TestValidate_RefusesMismatchedWorkloadHash, TestAblateJSONReport; go test ./cmd/fak",
      "entry_doc": "docs/benchmarks/ABLATE-RESULTS.md",
      "verdict": "usable-today",
      "gaps": [
        "Rung 1 sweeps only the runtime-settable vDSO knob; the ~40 env-gated features need the subprocess-re-exec rung (BuildSweep fails loud rather than measuring nothing)",
        "The live-loop and cross-agent arms are separate rungs"
      ],
      "durability_note": "All arms are bound to the trace's single workload hash by an N-arm identical-workload guard, so the deltas are apples-to-apples."
    },
    {
      "id": "cross-agent-ablation",
      "concept": "Cross-agent ablation (Regime B — bare claude -p vs fak guard -- claude -p)",
      "category": "performance",
      "surface": "subsystem",
      "what_you_get": "The first live cross-agent (Regime B) ablation: K=5 reps/arm on a fixed model measure what the fak guard hop costs an external agent. On the trivial pong task the guard was a net input-side cost (+input tokens from a reshaped prompt-cache split), reported honestly with its real sign — never spun as a saving.",
      "audience": "researcher",
      "maturity": "shipped",
      "claims_section": "Cross-agent ablation (Regime B — bare `claude -p` vs `fak guard -- claude -p`)",
      "claims_tag": "SHIPPED",
      "first_command": "",
      "first_command_verb": "",
      "needs_gpu": false,
      "needs_key": true,
      "witness_path": "experiments/ablate/cross-agent-pong-opus.json",
      "witness": "python tools/cross_agent_ablate_test.py (21 hermetic tests); every aggregate re-derives offline from raw_reps via tools/cross_agent_ablate.py report",
      "entry_doc": "docs/benchmarks/ABLATE-RESULTS.md",
      "verdict": "real-not-easy",
      "gaps": [
        "Live arm needs a real claude binary + an API key/account; only the committed-artifact report re-derives offline",
        "One tiny tool-light task on one host/account — distributional validity, not a fleet SLA; a denial-inducing multi-tool task and a pure_fak arm are follow-on rungs"
      ],
      "durability_note": "The controller enforces the validity contract: no saved number unless both arms completed AND succeeded, mean +/- CI95 over K>=5, model held constant across and within arms, tokens always decomposed (input/output/cache_read/cache_create), never summed."
    },
    {
      "id": "vcache-chains-recall-m4",
      "concept": "vCache Chains & Recall (M4)",
      "category": "performance",
      "surface": "benchmark",
      "what_you_get": "Run `fak vcache prove-recall` to exercise the prefix-DAG + cost-gated rebuild engine that decides, per recall, whether to replay a chain or send the unit cold — the default run refutes a single-unit rebuild (the 300x loss) and --siblings 301 proves the amortized fan-out exception.",
      "audience": "developer",
      "maturity": "shipped",
      "claims_section": "vCache Chains & Recall (M4)",
      "claims_tag": "SHIPPED",
      "first_command": "go run ./cmd/fak vcache prove-recall",
      "first_command_verb": "vcache",
      "needs_gpu": false,
      "needs_key": false,
      "witness_path": "internal/vcachechain",
      "witness": "TestProveRecall, TestPlanRecall, TestBreakEven, TestTopologicalReplay, TestPlaceBreakpoints; go test ./cmd/fak -run TestRunVCacheProveRecall",
      "entry_doc": "docs/notes/VCACHE-VIRTUAL-API-CACHE-2026-06-24.md",
      "verdict": "usable-today",
      "gaps": [
        "Gated off by default (DefaultEnabled=false) — every recall is sent cold until the live provider recall loop flips it on",
        "Off-path decision engine (prefix DAG + cost gate + replay scheduler), not the live provider recall transport (waits on M1-M3)"
      ],
      "durability_note": "Correctness never depends on the verdict (Law A2): whatever PlanRecall returns, the caller can always re-send the full prefix."
    },
    {
      "id": "vcache-governor-m5",
      "concept": "vCache Governor (M5)",
      "category": "performance",
      "surface": "benchmark",
      "what_you_get": "Run `fak vcache prove` (or prove-telemetry over a real Claude/Codex usage JSONL) to exercise the steady-state warm-set policy: pin/lazy/evict classification, a rate-safe warm budget, cross-shard affinity, and a Law-D4 secret classifier that refuses regulated content before any economics.",
      "audience": "developer",
      "maturity": "shipped",
      "claims_section": "vCache Governor (M5)",
      "claims_tag": "SHIPPED",
      "first_command": "go run ./cmd/fak vcache prove",
      "first_command_verb": "vcache",
      "needs_gpu": false,
      "needs_key": false,
      "witness_path": "internal/vcachegov",
      "witness": "go test ./internal/vcachegov ./cmd/fak -run \"TestRunVCache|TestProve\" (cutoff, warm-budget, affinity, secret refusal, OpenAI/Codex usage parsing); fak vcache prove-telemetry over committed live JSONL",
      "entry_doc": "docs/notes/VCACHE-VIRTUAL-API-CACHE-2026-06-24.md",
      "verdict": "usable-today",
      "gaps": [
        "Policy/decision layer plus cost proof only — correctness never depends on a provider cache hit; the live warming loop remains #716-#718",
        "Observed telemetry numbers are relayed from the provider's own cache counters (a realized rebate), not a fak-caused effect"
      ],
      "durability_note": "Below-minimum or unsafe-content workloads are first-class REFUTED outcomes; observed provider telemetry is reconciled from JSONL instead of assumed."
    }
  ]
}
