Every release, stress-tested
Beam runs next to, and inside, your applications, so each Beam CLI version is tested for what could hurt them before it ships: input built to stall its rules, memory over millions of log lines, AgentBeam being down or slow, and its CPU cap.
The test runs when the package is published, and a version that breaks a limit isn’t published. Its report ships inside the package, so what you see here was measured on that exact version. Run it yourself with npm run stress in the open-source CLI.
- Stress test passed
Measured October 25, 2026 on Apple M3 Pro (11 cores), Node v25.5.0, when the package was published
Hostile input
41 attack shapes at 16 KB; the slowest took 9.12 ms (unicode tags)
Limit: under 250 ms for any single 16 KB input
Pass
Package scanning, hostile files
17 attack shapes at 3 MB; the slowest took 202.2 ms (curl )
Limit: under 1 s for any single 3 MB file
Pass
Log throughput
38,479 log lines per second on one core, attacks included
Limit: over 10,000 lines per second
Pass
Cost per call in your app
request() 27 µs (46.6 µs with full headers and Cloudflare's bot fields), prompt() 14.1 µs on a short message
Limit: request() under 100 µs and prompt() under 200 µs
Pass
Memory under load (beam monitor)
9.9 MB at start; 13.2, 13.3, 12.4, 12.2, 11.9, 11.8 MB after each 500,000 lines; -1.5 MB from 1M to 3M lines
Limit: under 20 MB growth from 1M to 3M lines
Pass
Memory in your app while AgentBeam is down
8.6, 8.6, 8.6, 8.6 MB after each 250,000 requests and prompts
Limit: under 10 MB growth over 1M requests
Pass
AgentBeam down or slow
request() stayed at 23.3 µs; 1 send attempt, then none while backing off; a hung connection was dropped after 5.0 s, off the request path
Limit: no slowdown, no retries during backoff, hung sends dropped within 7 s
Pass
CPU cap
with a 1% cap (600 ms a minute), a flood of 200 KB documents got 643 ms of checking (61 documents); the rest were skipped, flagged as skipped, at 0.12 µs each
Limit: under twice the cap (one check can finish after the cap is reached)
Pass
- Stress test passed
Measured October 25, 2026 on Apple M3 Pro (11 cores), Node v25.5.0, when the package was published
Hostile input
41 attack shapes at 16 KB; the slowest took 9 ms (curl|)
Limit: under 250 ms for any single 16 KB input
Pass
Package scanning, hostile files
17 attack shapes at 3 MB; the slowest took 255.3 ms (ngrok)
Limit: under 1 s for any single 3 MB file
Pass
Log throughput
37,401 log lines per second on one core, attacks included
Limit: over 10,000 lines per second
Pass
Cost per call in your app
request() 26 µs (33.1 µs with full headers and Cloudflare's bot fields), prompt() 12.9 µs on a short message
Limit: request() under 100 µs and prompt() under 200 µs
Pass
Memory under load (beam monitor)
9.8 MB at start; 13, 13.2, 13.1, 12.2, 12.2, 11.7 MB after each 500,000 lines; -1.5 MB from 1M to 3M lines
Limit: under 20 MB growth from 1M to 3M lines
Pass
Memory in your app while AgentBeam is down
8.4, 8.4, 8.4, 8.4 MB after each 250,000 requests and prompts
Limit: under 10 MB growth over 1M requests
Pass
AgentBeam down or slow
request() stayed at 52.2 µs; 1 send attempt, then none while backing off; a hung connection was dropped after 5.0 s, off the request path
Limit: no slowdown, no retries during backoff, hung sends dropped within 7 s
Pass
CPU cap
with a 1% cap (600 ms a minute), a flood of 200 KB documents got 650 ms of checking (44 documents); the rest were skipped, flagged as skipped, at 0.12 µs each
Limit: under twice the cap (one check can finish after the cap is reached)
Pass
- Stress test passed
Measured October 24, 2026 on Apple M3 Pro (11 cores), Node v25.5.0, when the package was published
Hostile input
41 attack shapes at 16 KB; the slowest took 8.23 ms (unicode tags)
Limit: under 250 ms for any single 16 KB input
Pass
Package scanning, hostile files
17 attack shapes at 3 MB; the slowest took 175.3 ms (curl )
Limit: under 1 s for any single 3 MB file
Pass
Log throughput
39,822 log lines per second on one core, attacks included
Limit: over 10,000 lines per second
Pass
Cost per call in your app
request() 26.1 µs, prompt() 14.5 µs on a short message
Limit: request() under 100 µs and prompt() under 200 µs
Pass
Memory under load (beam monitor)
9.7 MB at start; 13, 13.1, 13, 13, 12.2, 11.7 MB after each 500,000 lines; -1.4 MB from 1M to 3M lines
Limit: under 20 MB growth from 1M to 3M lines
Pass
Memory in your app while AgentBeam is down
8.3, 8.3, 8.3, 8.3 MB after each 250,000 requests and prompts
Limit: under 10 MB growth over 1M requests
Pass
AgentBeam down or slow
request() stayed at 20.8 µs; 1 send attempt, then none while backing off; a hung connection was dropped after 5.0 s, off the request path
Limit: no slowdown, no retries during backoff, hung sends dropped within 7 s
Pass
CPU cap
with a 1% cap (600 ms a minute), a flood of 200 KB documents got 638 ms of checking (61 documents); the rest were skipped, flagged as skipped, at 0.11 µs each
Limit: under twice the cap (one check can finish after the cap is reached)
Pass
- Stress test passed
Measured October 24, 2026 on Apple M3 Pro (11 cores), Node v24.5.0, when the package was published
Hostile input
41 attack shapes at 16 KB; the slowest took 6.41 ms (unicode tags)
Limit: under 250 ms for any single 16 KB input
Pass
Package scanning, hostile files
17 attack shapes at 3 MB; the slowest took 135.3 ms (curl )
Limit: under 1 s for any single 3 MB file
Pass
Log throughput
79,283 log lines per second on one core, attacks included
Limit: over 10,000 lines per second
Pass
Cost per call in your app
request() 12.5 µs, prompt() 8.7 µs on a short message
Limit: request() under 100 µs and prompt() under 200 µs
Pass
Memory under load (beam monitor)
8.8 MB at start; 10.3, 10.4, 10.3, 10.4, 10.4, 10.4 MB after each 500,000 lines; +0 MB from 1M to 3M lines
Limit: under 20 MB growth from 1M to 3M lines
Pass
Memory in your app while AgentBeam is down
8.8, 8.8, 8.8, 8.8 MB after each 250,000 requests and prompts
Limit: under 10 MB growth over 1M requests
Pass
AgentBeam down or slow
request() stayed at 9 µs; 1 send attempt, then none while backing off; a hung connection was dropped after 5.0 s, off the request path
Limit: no slowdown, no retries during backoff, hung sends dropped within 7 s
Pass
CPU cap
with a 1% cap (600 ms a minute), a flood of 200 KB documents got 642 ms of checking (76 documents); the rest were skipped, flagged as skipped, at 0.08 µs each
Limit: under twice the cap (one check can finish after the cap is reached)
Pass
- Stress test passed
Measured October 23, 2026 on Apple M3 Pro (11 cores), Node v24.5.0, when the package was published
Hostile input
41 attack shapes at 16 KB; the slowest took 13.9 ms (unicode tags)
Limit: under 250 ms for any single 16 KB input
Pass
Log throughput
51,922 log lines per second on one core, attacks included
Limit: over 10,000 lines per second
Pass
Cost per call in your app
request() 16.1 µs, prompt() 11 µs on a short message
Limit: request() under 100 µs and prompt() under 200 µs
Pass
Memory under load (beam monitor)
8.5 MB at start; 9.9, 10.1, 10, 10, 10, 10 MB after each 500,000 lines; -0.1 MB from 1M to 3M lines
Limit: under 20 MB growth from 1M to 3M lines
Pass
Memory in your app while AgentBeam is down
8.4, 8.4, 8.4, 8.4 MB after each 250,000 requests and prompts
Limit: under 10 MB growth over 1M requests
Pass
AgentBeam down or slow
request() stayed at 13.4 µs; 1 send attempt, then none while backing off; a hung connection was dropped after 5.0 s, off the request path
Limit: no slowdown, no retries during backoff, hung sends dropped within 7 s
Pass
CPU cap
with a 1% cap (600 ms a minute), a flood of 200 KB documents got 642 ms of checking (59 documents); the rest were skipped, flagged as skipped, at 0.13 µs each
Limit: under twice the cap (one check can finish after the cap is reached)
Pass
Published before stress reports shipped with each release.
Published before stress reports shipped with each release.
Published before stress reports shipped with each release.
Published before stress reports shipped with each release.
Published before stress reports shipped with each release.
What changed in each version is in the changelog and the CLI’s commit history.