Rules, images, code, URLs — shrink what your AI sees while preserving meaning
CRUX extracts semantic cores. LLMs interpret it natively—no decompression, no special training.
CRUX captures meaning, not bytes. That principle extends to images — extract the semantic visual description, discard the pixels.
/crux-compress @path/to/image.png in Cursor
.crux.md file
.crux.md to any LLM with image generation
CRUX captures the semantic structure of code — function signatures, control flow, IO patterns — while stripping syntactic verbosity. LLMs reconstruct functionally equivalent code from the notation alone.
emulate=shellcheck tells LLMs which linting semantics to apply
Compress any public webpage into CRUX notation. Fetch, extract, compress — turn verbose documentation sites into token-efficient semantic cores.
A symbolic language LLMs interpret naturally. Click to explore.
⟦CRUX:source...⟧ | Block delimiters with source reference | ⟦CRUX:api.md ... ⟧ |
{k=v,k2=v2} | Object / map | {timeout=30,retries=3} |
[a,b,c] | List / array | [js,ts,py] |
.sub | Namespace (e.g., Π.core) | R.style{...} |
; | Statement separator | a=1; b=2 |
> | Greater than | size>100 |
< | Less than | len<50 |
≥ | Greater or equal | version≥2.0 |
≤ | Less or equal | line≤100ch |
≠ | Not equal | status≠deleted |
.. | Range | port=8000..9000 |
≻ | Preferred over / takes precedence | CONFIRMED≻DRAFT |
≺ | Ranks below / lower priority | optional≺required |
→ | Flows to / maps to / then | ∀changes→run_tests |
← | Flows from / derives from | config←env_vars |
» | Then / next step / sequential | parse»validate»save |
⊳ | Has domain/expertise | agent⊳security |
⊲ | Triggered by / activated on | hook⊲commit |
@ | Located at path | config@/etc/app |
: | Has type / key-value | port:number |
= | Equals / defined as | max=100 |
∋ | Contains / includes | deps∋[react,vue] |
| | OR / alternatives | format=json|yaml |
& | AND / conjunction | valid&complete |
⊤ | True / enabled | debug=⊤ |
⊥ | False / disabled | cache=⊥ |
∀ | For all / universal | ∀files→lint |
∃ | Exists / some | ∃config→load |
¬ | Not / negation | ¬tabs! |
Δ | Change / update / delta | Δschema→migrate |
+ | Add / include / with | +tests,+docs |
- | Remove / exclude | -node_modules |
* | Many / collection | files*→process |
? | Optional | config? |
! | Required / important | auth! |
# | Comment / note | #deprecated |
⊕ | Optimal / target | ⊕performance |
⊛ | Critical / highest importance | ⊛security_check |
◊ | Lowest importance / trivial | ◊formatting |
Ρ{...} | Repository/project context | Ρ{api server} |
E{...} | Entities (agents, components) | E{user,admin} |
Λ{...} | Commands/actions | Λ{build,test,deploy} |
Π{...} | Architecture (modules) | Π{src/,lib/} |
Κ{...} | Concepts/definitions | Κ{token=JWT} |
R{...} | Requirements/guidelines | R{∀fn→test} |
P{...} | Policies/constraints | P{¬force push} |
Γ{...} | Orchestration (workflows) | Γ{ci»cd»deploy} |
M{...} | Memory/state | M{session,cache} |
Φ{...} | Configuration | Φ{port=3000} |
Ω{...} | Quality gates | Ω{cov≥80%} |
Prerequisites: curl, unzip, Cursor IDE
curl -fsSL https://raw.githubusercontent.com/zotoio/CRUX-Compress/main/install.sh | bashCRUX.mdSpecification (readonly)AGENTS.mdAgent awareness notice.cursor/rules/_CRUX-RULE.mdcAlways-applied rule.cursor/agents/crux-cursor-rule-manager.mdCompression agent.cursor/commands/crux-compress.mdCompression command.cursor/hooks/crux-detect-changes.shChange detection hook.cursor/hooks/crux-session-start.shSession start hook.cursor/skills/crux-utils/Utility skill.crux/crux.jsonVersion trackercrux: true to your rule file's frontmatter
/crux-compress ALL in Cursor
Optional: add command-parameter plugins with
/crux-compress ALL --plugin quality-gate.