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# [AI by Hand ✍️](https://www.byhand.ai/)
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LatestTopDiscussions
[RNNs by Hand, in Excel](https://www.byhand.ai/p/library-series-sheets-rnn)
[From a small neuron to a small language model](https://www.byhand.ai/p/library-series-sheets-rnn)
Sep 27 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/013.jpeg)
[Small Language Model](https://www.byhand.ai/p/library-sheets-rnn-everything)
[RNNs by Hand, in Excel](https://www.byhand.ai/p/library-sheets-rnn-everything)
Sep 27 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/031.jpeg)
[Loss](https://www.byhand.ai/p/library-sheets-rnn-loss)
[RNNs by Hand, in Excel](https://www.byhand.ai/p/library-sheets-rnn-loss)
Sep 27 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/body-71b03f8628af53f6a41c.jpeg)
[Autoregressive](https://www.byhand.ai/p/library-sheets-rnn-autoregressive)
[RNNs by Hand, in Excel](https://www.byhand.ai/p/library-sheets-rnn-autoregressive)
Sep 27 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/body-2b6c199cfb9f8d1b0908.jpeg)
[Tokens](https://www.byhand.ai/p/library-sheets-rnn-tokens)
[RNNs by Hand, in Excel](https://www.byhand.ai/p/library-sheets-rnn-tokens)
Sep 27 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/body-cfeab5d9caafe940992a.jpeg)
[Seq2Seq](https://www.byhand.ai/p/library-sheets-rnn-seq2seq)
[RNNs by Hand, in Excel](https://www.byhand.ai/p/library-sheets-rnn-seq2seq)
Sep 27 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/body-6893cd6ea589e38ea314.jpeg)
[Depth](https://www.byhand.ai/p/library-sheets-rnn-depth)
[RNNs by Hand, in Excel](https://www.byhand.ai/p/library-sheets-rnn-depth)
Sep 27 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/body-9286230f5d89b79c2d42.jpeg)
[Outputs](https://www.byhand.ai/p/library-sheets-rnn-outputs)
[RNNs by Hand, in Excel](https://www.byhand.ai/p/library-sheets-rnn-outputs)
Sep 27 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/body-cc10f91b37b3f33d7144.jpeg)
[Size](https://www.byhand.ai/p/library-sheets-rnn-size)
[RNNs by Hand, in Excel](https://www.byhand.ai/p/library-sheets-rnn-size)
Sep 27 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/body-18aa0c4d64ad68ad40fb.jpeg)
[Recurrence](https://www.byhand.ai/p/library-sheets-rnn-recurrence)
[RNNs by Hand, in Excel](https://www.byhand.ai/p/library-sheets-rnn-recurrence)
Sep 27 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/body-615486b632cb86aff7d4.jpeg)
[AI by Hand ✍️ Yantra Jnana Award](https://www.byhand.ai/p/library-newsletter-challenges-yantra-jnana-challenge)
[Teach AI by Hand in India’s Languages](https://www.byhand.ai/p/library-newsletter-challenges-yantra-jnana-challenge)
Sep 4 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
25
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![](../images/body-194ac803361a1f80393d.jpeg)
### August 2026
[Counting AI by Hand ✍️ ~ Recordings](https://www.byhand.ai/p/library-series-videos-counting-ai-by-hand)
[Mohsena Ashraf on measuring what AI costs, in Excel](https://www.byhand.ai/p/library-series-videos-counting-ai-by-hand)
Aug 22 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
31
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![](../images/body-81461de8e2501d5dab4c.jpeg)
[Loop Engineering (coming soon, Sep 3, 2026)](https://www.byhand.ai/p/library-videos-counting-ai-by-hand-loop-engineering)
[Counting AI by Hand ✍️ Lecture Series by Mohsena](https://www.byhand.ai/p/library-videos-counting-ai-by-hand-loop-engineering)
Aug 22 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
3
[Agent Tokens (Jul 14, 2026)](https://www.byhand.ai/p/library-videos-counting-ai-by-hand-agent-tokens)
[Counting AI by Hand ✍️ Lecture Series by Mohsena](https://www.byhand.ai/p/library-videos-counting-ai-by-hand-agent-tokens)
Aug 22 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
3
1
![](../images/body-febaf3b8c4ed9512620e.jpeg)
[Transformer Ops (Jun 23, 2026)](https://www.byhand.ai/p/library-videos-counting-ai-by-hand-transformer-ops)
[Counting AI by Hand ✍️ Lecture Series by Mohsena](https://www.byhand.ai/p/library-videos-counting-ai-by-hand-transformer-ops)
Aug 22 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
2
1
![](../images/body-81461de8e2501d5dab4c.jpeg)
[Kimi 3 ~ New Seminar Recording](https://www.byhand.ai/p/library-videos-seminars-2026-kimi-3-seminar-recording)
[AI by Hand ✍️ Seminars](https://www.byhand.ai/p/library-videos-seminars-2026-kimi-3-seminar-recording)
Aug 20 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
29
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2
![](../images/body-a093b0c0f3afcb809354.jpeg)
[Context Problems](https://www.byhand.ai/p/library-series-agents-context)
[Agentic AI by hand ✍️](https://www.byhand.ai/p/library-series-agents-context)
Aug 19 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
3
1
![](../images/body-813351e60b94e92f7513.jpeg)
[Cost Forecast](https://www.byhand.ai/p/library-agents-context-a-long-conversation)
[Budgeting a Long Session](https://www.byhand.ai/p/library-agents-context-a-long-conversation)
Aug 19 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
2
![](../images/body-389b7d711514a7745d1b.jpeg)
[Quadratic Cost](https://www.byhand.ai/p/library-agents-context-adding-up-the-turns)
[Adding Up the Turns](https://www.byhand.ai/p/library-agents-context-adding-up-the-turns)
Aug 19 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
2
![](../images/body-27584192387e1d43b8f7.jpeg)
[Context Tax](https://www.byhand.ai/p/library-agents-context-paying-for-the-past)
[Paying for the Past](https://www.byhand.ai/p/library-agents-context-paying-for-the-past)
Aug 19 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
2
![](../images/body-a33cbf83340d5f789c46.jpeg)
[Retrieval Cost](https://www.byhand.ai/p/library-agents-context-retrieved-chunks-are-input)
[Retrieved Chunks Are Input](https://www.byhand.ai/p/library-agents-context-retrieved-chunks-are-input)
Aug 19 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
1
![](../images/body-48ff7aa014e712ce707a.jpeg)
[Stateless API](https://www.byhand.ai/p/library-agents-context-what-each-turn-sends)
[Resending the Context](https://www.byhand.ai/p/library-agents-context-what-each-turn-sends)
Aug 19 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
2
![](../images/body-8697823432decfe4082b.jpeg)
[Verbatim Tail](https://www.byhand.ai/p/library-agents-context-what-compaction-keeps)
[Keeping the recent rounds whole](https://www.byhand.ai/p/library-agents-context-what-compaction-keeps)
Aug 19 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/body-d0049c0aeb795c41de72.jpeg)
[The Compaction Threshold](https://www.byhand.ai/p/library-agents-context-when-to-compact)
[Picking the number from a round](https://www.byhand.ai/p/library-agents-context-when-to-compact)
Aug 19 • [Prof. Tom Yeh](https://substack.com/@tomyeh)
![](../images/body-ffcce59723a05cf35ddc.jpeg)
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