CliMA

Maintains the Python dependencies of the CalibrateEmulateSample.jl (CES) Julia repository, which are managed through CondaPkg.jl + PythonCall.jl. Use this skill whenever the user wants to: change/pin/bump/downgrade the versions of Python, scikit-learn, or scipy in CES (via CondaPkg.toml); resolve Julia-side version conflicts involving CondaPkg or PythonCall (e.g. `Pkg.update` won't move PythonCall, compat-bound errors, a stale Manifest after a dep bump); debug Python import / environment failures ("sklearn could not be imported", CondaPkg env out of sync); rename or deprecate a Julia type that wraps the Python backend; or update docs/src/installation_instructions.md to match the current Python setup. Trigger it even without the word "CondaPkg" — cues like "bump scikit-learn", "update PythonCall", "the python env is stale", "change the python version", "CES can't find sklearn", or "add a deprecation notice" all apply.

Add concise Base.show and Base.summary methods to Julia types whose default REPL representation is unhelpful or overwhelming. Use this skill whenever the user mentions that a type prints badly in the REPL, asks to improve how an object is displayed or printed, wants a custom show, summary, or repr for a Julia type, or says the REPL output is noisy, verbose, or hard to read. Also trigger when the user asks to "make the REPL output nicer", "add a show method", "add a summary method", "customize display", or "fix what prints when I type a variable name". This skill produces compact, informative Base.show and Base.summary methods and matching unit tests — invoke it proactively whenever show, summary, display, print, repr, or REPL output is mentioned in a Julia context.

Add or normalise Julia docstrings on public symbols (exported types, functions, and constants) so the package's public API is fully self-documenting and the Documenter.jl docs build passes its checkdocs check. After writing docstrings, also updates docs/src/API/ pages so every exported symbol appears exactly once, organised into logical categories, with stale entries removed. Invoke this skill whenever the user mentions: docstring, missing doc, undocumented symbol, API doc, checkdocs warning, docs/src/API, @docs block, or asks to document a type or function, sync the API pages, or keep the API index up to date. Also use it when the user asks to "write docs for" or "add docs to" source files, or when a CI failure mentions missing or incomplete docstrings.

Rewrite vague, delayed, or low-context Julia error messages into structured, actionable diagnostics. Invoke this skill whenever the user mentions: error message, improve errors, rewrite @assert, ArgumentError, DimensionMismatch, DomainError, vague error, error rewrite, Julia exception, diagnostic, throw, validation, early check, assert to throw, loop context, catch and rethrow, warn string, or asks to improve how the code fails. Also use it when reviewing code for user-facing clarity, when a user says errors are confusing or unhelpful, or when auditing a module for low-context exceptions. Use it proactively when you see bare @assert, error("..."), throw(ErrorException(...)), @warn string(...), or catch blocks that do not include the original exception in their re-throw in Julia code you are reading or editing.

Add concise Base.show and Base.summary methods to Julia types whose default REPL representation is unhelpful or overwhelming. Use this skill whenever the user mentions that a type prints badly in the REPL, asks to improve how an object is displayed or printed, wants a custom show, summary, or repr for a Julia type, or says the REPL output is noisy, verbose, or hard to read. Also trigger when the user asks to "make the REPL output nicer", "add a show method", "add a summary method", "customize display", or "fix what prints when I type a variable name". This skill produces compact, informative Base.show and Base.summary methods and matching unit tests — invoke it proactively whenever show, summary, display, print, repr, or REPL output is mentioned in a Julia context.

Add or normalise Julia docstrings on public symbols (exported types, functions, and constants) so the package's public API is fully self-documenting and the Documenter.jl docs build passes its checkdocs check. After writing docstrings, also updates docs/src/API/ pages so every exported symbol appears exactly once, organised into logical categories, with stale entries removed. Invoke this skill whenever the user mentions: docstring, missing doc, undocumented symbol, API doc, checkdocs warning, docs/src/API, @docs block, or asks to document a type or function, sync the API pages, or keep the API index up to date. Also use it when the user asks to "write docs for" or "add docs to" source files, or when a CI failure mentions missing or incomplete docstrings.

Rewrite vague, delayed, or low-context Julia error messages into structured, actionable diagnostics. Invoke this skill whenever the user mentions: error message, improve errors, rewrite @assert, ArgumentError, DimensionMismatch, DomainError, vague error, error rewrite, Julia exception, diagnostic, throw, validation, early check, assert to throw, loop context, catch and rethrow, warn string, or asks to improve how the code fails. Also use it when reviewing code for user-facing clarity, when a user says errors are confusing or unhelpful, or when auditing a module for low-context exceptions. Use it proactively when you see bare @assert, error("..."), throw(ErrorException(...)), @warn string(...), or catch blocks that do not include the original exception in their re-throw in Julia code you are reading or editing.

Add concise Base.show and Base.summary methods to Julia types whose default REPL representation is unhelpful or overwhelming. Use this skill whenever the user mentions that a type prints badly in the REPL, asks to improve how an object is displayed or printed, wants a custom show, summary, or repr for a Julia type, or says the REPL output is noisy, verbose, or hard to read. Also trigger when the user asks to "make the REPL output nicer", "add a show method", "add a summary method", "customize display", or "fix what prints when I type a variable name". This skill produces compact, informative Base.show and Base.summary methods and matching unit tests — invoke it proactively whenever show, summary, display, print, repr, or REPL output is mentioned in a Julia context. Good candidates in RandomFeatures.jl include Decomposition, ScalarFeature, VectorFeature, RandomFeatureMethod, and Fit — all of which hold matrices or nested objects that print poorly by default.

Add or normalise Julia docstrings on public symbols (exported types, functions, and constants) so the package's public API is fully self-documenting and the Documenter.jl docs build passes its checkdocs check. After writing docstrings, also updates docs/src/API/ pages so every exported symbol appears exactly once, organised into logical categories, with stale entries removed. Invoke this skill whenever the user mentions: docstring, missing doc, undocumented symbol, API doc, checkdocs warning, docs/src/API, @docs block, or asks to document a type or function, sync the API pages, or keep the API index up to date. Also use it when the user asks to "write docs for" or "add docs to" source files, or when a CI failure mentions missing or incomplete docstrings. In RandomFeatures.jl, the 2026-05-20 audit resolved all bare stubs; common failure modes to watch for are inaccurate return-type claims, getter prose copy-pasted across dispatches, and jldoctests using `using PackageName` for symbols that live only in a submo

Rewrite vague, delayed, or low-context Julia error messages into structured, actionable diagnostics. Invoke this skill whenever the user mentions: error message, improve errors, rewrite @assert, ArgumentError, DimensionMismatch, DomainError, vague error, error rewrite, Julia exception, diagnostic, throw, validation, early check, assert to throw, loop context, catch and rethrow, warn string, or asks to improve how the code fails. Also use it when reviewing code for user-facing clarity, when a user says errors are confusing or unhelpful, or when auditing a module for low-context exceptions. Use it proactively when you see bare @assert, error("..."), throw(ErrorException(...)), @warn string(...), or catch blocks that do not include the original exception in their re-throw in Julia code you are reading or editing.