SWE-bench Verified, live, four arms: 13% cheaper than no compaction, and the highest reward. See the numbers
Full results — baseline (Terminal-Bench 2.0, 89 tasks)¶
Baseline arm: no compaction — the claude-code agent on aws/claude-sonnet-5, run LIVE through the harness against Terminal-Bench 2.0's 89 tasks. Routing goes through the context-guru off transparent passthrough proxy (identical plumbing to the compaction arms; zero content change), so this is the like-for-like reference the framework arms are measured against. Cache-aware billed input cost (fresh $2/M · cache-read $0.20/M · cache-write $2.50/M) + output $10/M, recomputed from each trial's own token tiers — the same model as the SWE-bench study. See REPRODUCE.md.
* mean steps over the 82 completed tasks (timed-out runs are truncated). Solve rate over completed-only tasks: 56/82 = 68.3%.
Time-budget policy. Wall-clock budget = the task-authored timeout × a multiplier. Most tasks ran at 1.5×; the long-horizon tasks that first timed out were retried at low concurrency and, if still short, given an extended 4× budget (up to ~4 h) to measure capability rather than a latency-truncated result. 3 tasks solved only under the 4× budget (counted as solved here); the 7 below exhausted even 4×.
Terminal-Bench 2.0 is a much harder, longer-horizon benchmark than SWE-bench Verified. The
baseline solves 62.9% of tasks vs 86% on SWE-bench, at ~$1.13/task (vs $0.64) and ~1.7M
prompt tokens/task — TB tasks are open-ended terminal goals (build/compile/train/exploit), not a
localized patch, so the agent runs longer and reads far more.
Difficulty is the dominant axis. Easy/medium solve at 71–75%; hard drops to 47% and
costs 3.4× more per task ($2.04 vs $0.61). Every one of the 7 unrecoverable timeouts is a
hard/long task.
Category tells the same story from the other side. The agent is reliable on bounded,
verifiable goals — debugging (100%), system-administration (78%), security (75%),
data-processing/model-training (75%) — and weak on sprawling build/implement tasks:
software-engineering (38%, the largest bucket at 26 tasks) and video-processing (0%).
It is still a ~98%-cached agent (98.2% cache-hit), so — exactly as on SWE-bench —
cache-read is the single biggest cost term (43% of the bill). That is the lever the compaction
arms must pull; a layer that shrinks the cached context should move TB cost the same way it moved
SWE cost.
Latency, not just capability, caps the ceiling. The gateway's ~26 s/request (5–10× a normal
endpoint) means long-horizon tasks can run out of wall-clock before finishing. 3 tasks that first
timed out solved once given a 4× budget — so 62.9% is a floor, and a compaction arm that
reduces round-trips could recover more of the remaining 7. The timeout count is therefore itself a
comparison metric, not just noise.
Token & cost accounting (cache-aware, all 89 tasks)¶
tier
tokens
$/M
billed
cache-read (input)
215,971,427
0.20
$43.19
cache-write (input)
4,011,068
2.50
$10.03
fresh (input)
58,893
2.00
$0.12
completion (output)
4,746,887
10.00
$47.47
total
$100.81
Cache-read is 43% of the bill at a 98.2% cache-hit rate — as on SWE-bench, a heavily-cached agent, so the lever a compaction layer must pull is cache-read tokens.
These tasks still hit the wall-clock budget under the extended 4× timeout (up to ~4 h each) and scored reward 0 — counted as failures in the solve rate above. A large part of the cause is gateway latency, not only agent capability: Terminal-Bench's timeouts assume a fast endpoint (~2–5 s/request), but this IBM LiteLLM gateway runs ~26 s/request (5–10× slower), so long-horizon tasks that need many round-trips run out of clock (concurrency is not the cause — latency was flat ~23–30 s/req from n=1 to n=24). They are all hard/long software-engineering and compute tasks (path-tracing, a MIPS Doom port, a metacircular evaluator, COBOL modernization, GPT-2 code-golf, CIFAR training). A compaction arm that cuts round-trips could bring some under budget, so the timeout count is itself a comparison metric.
task
difficulty
category
steps before timeout
partial billed
budget (4×)
caffe-cifar-10
medium
machine-learning
12
$0.24
80 min
cobol-modernization
easy
software-engineering
133
$5.11
60 min
gpt2-codegolf
hard
software-engineering
43
$1.48
60 min
make-doom-for-mips
hard
software-engineering
160
$6.39
60 min
path-tracing-reverse
hard
software-engineering
170
$9.62
120 min
schemelike-metacircular-eval
medium
software-engineering
74
$4.37
160 min
write-compressor
hard
software-engineering
6
$0.36
60 min
By difficulty (all 89 tasks; timeouts = failures)¶