BEAM leaderboard
BEAM (Beyond a Million Tokens, Tavakoli et al., ICLR 2026) measures long-term memory in AI agents. It asks 2,000 questions over 100 conversations at four history sizes: 100K, 500K, 1M and 10M tokens. Harny scores 85.1 at the 128K tier, the best published score there.
BEAM accuracy by history size
Harny’s BEAM results by history size.
| System | 100K | 500K | 1M | 10M | Source |
|---|---|---|---|---|---|
| Harny | 85.1 | — | — | — | harny.ai |
How to read the table
Harny’s figure is a full BEAM split: all 400 questions at the 128K tier, across all ten abilities, scored on BEAM’s own rubric with the judge gemini-3.5-flash-lite.
Results at each size
Harny’s results at the history size measured. For every other published result at each size, use the public leaderboard.
100K tokens
| System | Accuracy | Source |
|---|---|---|
| Harny | 85.1 | harny.ai |
Results published in research papers
These results come from the BEAM paper itself, at the same smallest tier.
| System | Size | Accuracy | Paper |
|---|---|---|---|
| LIGHT, the BEAM paper’s own method | 100K | 35.8 | Tavakoli et al., 2026 |
| RAG baseline | 100K | 32.3 | Tavakoli et al., 2026 |
What BEAM measures
BEAM holds long conversations at four sizes and asks questions whose answers sit somewhere in that history. Each question tests one of ten abilities: abstention, contradiction resolution, event ordering, information extraction, instruction following, knowledge update, multi-session reasoning, preference following, summarization, temporal reasoning.
| History size | Conversations | Questions |
|---|---|---|
| 100K tokens | 20 | 400 |
| 500K tokens | 35 | 700 |
| 1M tokens | 35 | 700 |
| 10M tokens | 10 | 200 |
Another benchmark named BEAM
Eywa (Joshi, 2026) reports results on a 700-question technical-memory benchmark that is also called BEAM. It is a different benchmark from the one on this page, and its scores are not comparable to the results here. Eywa on arXiv →
Run it on your data
Ask Harny about changed facts, earlier sessions and questions your history cannot answer.