Scala — 128 Operations for AI Agents
This page is the canonical reference an AI coding agent uses to refactor, query, and analyze Scala code through the act MCP server. 128 operations available: 54 refactor, 18 query, 42 analysis, 14 verification. Each operation is callable from Claude Code, Cursor, Codex, OpenCode, or any MCP-compatible agent host. Click any operation for a stable anchor link suitable for citation.
Query
18 query tools, the same on every supported language. Descriptions live in the shared reference: /docs/query-tools.
callers control_flow data_flow definition diagnostics effect_closure effect_summary fix_auto get_type graph import_organize interface mutations references repo_outline skeleton symbols symbols_batch
Refactor
| Operation | Description |
|---|---|
add-access-modifier |
Add access modifier (private/protected/public) |
add-default-parameter |
Add default value to parameter |
add-import |
Add missing import statement |
add-missing-match-case |
Add missing case to pattern match |
add-result-type-annotation |
Add explicit return type to function |
change-visibility |
Change access modifier |
convert-class-to-case-class |
Convert class to case class |
convert-concat-to-interpolation |
Convert string concatenation to s-string interpolation |
convert-for-to-foreach |
Convert for comprehension to foreach call |
convert-foreach-to-for |
Convert foreach call to for comprehension |
convert-function-to-method |
Convert function to class method |
convert-ifelse-to-match |
Convert if-else chain to pattern match |
convert-loop-to-comprehension |
Convert for loop to for-comprehension with yield |
convert-map-filter-to-comprehension |
Convert map/filter chain to for-comprehension |
convert-method-to-function |
Convert method to standalone function |
convert-var-to-val |
Convert mutable var to immutable val |
explicit-type-annotation |
Add explicit type annotation |
extract-constant |
Extract value to named constant |
extract-function |
Extract code block into new function |
extract-interface |
Extract interface from class methods |
extract-method |
Extract code into a new method |
extract-variable |
Extract expression to variable |
extract_function |
Extract a code selection into a new function — automatically infers parameters, return types, and inserts the call site. Use instead of manually cutting/pasting code. Works without LSP; LSP improves type inference. Params: file (string), new_name (string), start_line (u32), start_column (u32), end_line (u32), end_column (u32) [, preview (bool), receipt (bool)] |
extract_variable |
Extract an expression into a named variable — inserts the declaration and replaces the expression with the variable name. Works without LSP. Params: file (string), new_name (string), start_line (u32), start_column (u32), end_line (u32), end_column (u32) [, preview (bool)] |
generate-accessors |
Generate getter for field |
generate-case-class-boilerplate |
Generate case class from existing class |
generate-constructor |
Generate constructor |
generate-copy-method |
Generate copy method for a class |
generate-equals |
Generate equals and hashCode methods |
generate-match-cases |
Generate pattern match cases |
generate-sealed-subclasses |
Generate subclasses for sealed trait/class |
generate-setter |
Generate setter for field |
generate-tests |
Generate unit test scaffold |
generate-to-string |
Generate toString method |
generate-trait-implementation |
Generate trait implementation with method stubs |
implement-sealed-subclass |
Generate case class subclass for sealed trait/class |
import-alias |
Add alias to import |
import-organize |
Sort and deduplicate imports |
import-remove |
Remove unused import |
initialize-field |
Add initialization to an uninitialized field |
inline |
Inline a variable, function, or method — replace every usage with its definition body, then remove the original. The inverse of extract. Works without LSP (single-file); LSP enables cross-file inlining. Params: file (string), symbol (string) [, line (u32), preview (bool), receipt (bool)] |
inline-function |
Inline function call into call site |
inline-variable |
Inline variable at all references |
insert_body |
Replace a function's implementation body with new code. AST-validated — rejects if the result has parse errors, so you can't accidentally break syntax. Use instead of manual text editing for function rewrites. Params: file (string), symbol (string), code (string) [, commit (bool)] |
introduce-field |
Promote variable to class field |
move |
Move class or method to another file |
move_symbol |
Move a function, class, or type to a different file and automatically update all imports across the codebase. Use instead of manually cut/paste + fixing imports. Works without LSP (single-file); LSP enables cross-file import updates. Params: file (string), symbol (string), destination (string) [, preview (bool), receipt (bool)] |
recipe_run |
Run a codemod recipe: declarative match → transform → optional verify across modeled grammars. Preview lists matches; apply writes with optional E7 receipts and all-or-nothing rollback. Returns a per-site report. |
remove-result-type-annotation |
Remove redundant return type |
remove-type-annotation |
Remove redundant type annotation |
rename |
Rename a symbol and automatically update ALL references across the codebase. Safer and faster than find-and-replace — AST-aware, won't rename strings or comments. Works without LSP (single-file); LSP enables cross-file renames. Params: file (string), old_name (string), new_name (string) [, line (u32), column (u32), preview (bool), receipt (bool)] |
rename |
Rename symbol and all references |
split-declaration-and-assignment |
Split declaration and assignment |
wrap-null-check |
Wrap expression in null-safe check |
Analysis
42 analysis tools, the same on every supported language. Descriptions live in the shared reference: /docs/analysis-tools.
analyze_api_diff analyze_chokepoints analyze_clones analyze_clusters analyze_cohesion analyze_conformance analyze_coupling analyze_cycle_risk analyze_cycles analyze_dead_code analyze_depth analyze_entry_points analyze_export analyze_extraction analyze_fan_balance analyze_features analyze_hotspots analyze_impact analyze_inconsistencies analyze_inheritance analyze_interface_bloat analyze_interfaces analyze_layers analyze_orphan_types analyze_patterns analyze_platform_deps analyze_readiness analyze_roles analyze_seams analyze_stability analyze_surface analyze_test_gaps analyze_thickness analyze_type_completeness churn_hotspots co_change_clusters coverage_overlay ownership_map profile_overlay simulate split_module trace_overlay
Verify
14 verify tools, the same on every supported language. Descriptions live in the shared reference: /docs/verification.
bisect_regression gate generate_test_harness scan secret_surface summarize_pr taint_flow unsafe_surface verify_behavioral_equivalence verify_contract_preserved verify_diff_semantics verify_port_parity verify_side_effects verify_test_impact