
TransformerLens Interpretability
Lets an agent inspect and edit transformer model internals for mechanistic interpretability research.
- Repository
- Orchestra-Research/AI-Research-SKILLs
- Stars
- 14,195
- Licence
- MIT
- Files
- 4 files
What it does
Teaches the agent how to use the TransformerLens Python library to open up language models like GPT-2 and look inside them. The agent can cache internal activations, study attention patterns, run activation patching experiments to find which parts of a model cause a behaviour, and do direct logit attribution. The skill gives code patterns, a list of supported models, and a checklist for these experiments, so the agent writes correct research code instead of guessing at the API.
Great for
- Researchers studying how transformer models compute specific behaviours such as indirect object identification
- Students learning mechanistic interpretability who want guided, runnable examples
- ML engineers who need to cache and inspect intermediate activations in GPT-style models
Skip it if
- Non-transformer architectures, which the skill itself says should use nnsight or pyvene instead, because TransformerLens targets transformer models
- Production safety decisions or auditing a deployed model without expert review, since the skill only supplies research techniques and does not validate findings
- Users without a Python environment and GPU access, since model loading and patching on larger models need substantial compute
Try asking
- “Run activation patching on GPT-2 small to find which layers and positions change the prediction from Rome to Paris”
- “Cache the residual stream and attention patterns for a prompt and plot a layer-by-position heatmap”
- “Reproduce the indirect object identification circuit analysis on gpt2-small with direct logit attribution”
- “Explain what the HookedTransformer activation cache keys like resid_post and pattern mean”
Install in 3 steps
- 1
Download the skill
The ZIP contains the 4 original files, the MIT licence and an attribution note.
transformer-lens.zip - 2
Add it to your agent
Claude Code (all projects)
mkdir -p ~/.claude/skills && unzip transformer-lens.zip -d ~/.claude/skills/Claude Code / Agent SDK (this project only)
mkdir -p .claude/skills && unzip transformer-lens.zip -d .claude/skills/Claude apps (web/desktop): Settings → Capabilities → Skills → Upload skill, and choose the ZIP.
- 3
Ask for the task
No special command needed — the agent reads the skill's description and loads it when your request matches. Try one of the prompts above.
Get better results
- Start with gpt2-small, which is small enough to run on a laptop or free GPU, before trying larger models
- Use names_filter in run_with_cache to cache only the activations you need, which saves a lot of memory
- Keep your Hugging Face token out of shared code; the example sets it as a plain string, so use an environment variable or secret store instead
What's inside
- references/api.md
- references/README.md
- references/tutorials.md
- SKILL.md
Redistributed unmodified from Orchestra-Research/AI-Research-SKILLs under the MIT licence. The assessment was drafted with AI from the skill's files on 2026-10-29. Skills can instruct your agent to run code — read SKILL.md and any scripts before installing.