| name | americanize |
| description | Converts British English spelling to American English in a file or directory. Scans text files for common British variants and rewrites them in-place. Accepts a file path or directory path as $ARGUMENTS. |
| argument-hint | <file-or-directory-path> |
| disable-model-invocation | true |
| allowed-tools | ["Read","Edit","Glob","Grep","Bash(find *)"] |
| model | sonnet |
Americanize
Convert British English spelling to American English across a file or directory.
File Operation Rules
Read and follow .agents/skills/file-operations/SKILL.md.
Your Task
Scan the target path for British English spelling variants and replace them with American English equivalents.
Edit files in-place. Report a summary of what changed.
Steps
1. Resolve Target Path
Read $ARGUMENTS. If empty, tell the user to provide a file or directory path and exit.
The path may be absolute or relative. Treat it as-is.
2. Collect Files to Scan
If the target is a single file: scan that file only.
If the target is a directory: use Glob to collect all text files recursively. Skip binary files and these
paths regardless of content:
*.png, *.jpg, *.jpeg, *.gif, *.webp, *.svg, *.ico
*.pdf, *.zip, *.tar, *.gz, *.woff, *.woff2, *.ttf, *.eot
*.lock (e.g. composer.lock, package-lock.json, yarn.lock)
node_modules/, vendor/, .git/
3. Scan and Replace
For each collected file, use Grep to check if any British spellings are present before reading.
Only read and edit files that have at least one match.
Apply all substitutions from the reference table below. Replacements are case-sensitive and
case-preserving: match the casing pattern of the found word and apply the same pattern to the replacement.
Casing patterns to handle for each substitution:
| Found form | Replace with |
|---|
word | word |
Word | Word |
WORD | WORD |
Do NOT alter words inside URLs, import paths, package names, or version strings (e.g. node_modules,
colour-js, en-GB locale identifiers). Use judgment — if changing the spelling would break a reference to
an external identifier, skip it.
4. British → American Reference Table
Apply every substitution in this table. This list is not exhaustive — use it as a seed. If you encounter an
obvious British variant not listed here, apply the correct American spelling.
-our → -or
| British | American |
|---|
| colour | color |
| colours | colors |
| coloured | colored |
| colouring | coloring |
| colourful | colorful |
| behaviour | behavior |
| behaviours | behaviors |
| behavioural | behavioral |
| favour | favor |
| favours | favors |
| favoured | favored |
| favourite | favorite |
| favourites | favorites |
| flavour | flavor |
| flavours | flavors |
| honour | honor |
| honours | honors |
| honourable | honorable |
| humour | humor |
| humours | humors |
| humorous | humorous |
| labour | labor |
| labours | labors |
| neighbour | neighbor |
| neighbours | neighbors |
| neighbourhood | neighborhood |
| rumour | rumor |
| rumours | rumors |
| saviour | savior |
| tumour | tumor |
| tumours | tumors |
| vapour | vapor |
| vigour | vigor |
-ise → -ize / -isation → -ization
| British | American |
|---|
| organise | organize |
| organises | organizes |
| organised | organized |
| organising | organizing |
| organisation | organization |
| organisations | organizations |
| organisational | organizational |
| recognise | recognize |
| recognises | recognizes |
| recognised | recognized |
| recognising | recognizing |
| recognisable | recognizable |
| authorise | authorize |
| authorises | authorizes |
| authorised | authorized |
| authorising | authorizing |
| authorisation | authorization |
| authorisations | authorizations |
| realise | realize |
| realises | realizes |
| realised | realized |
| realising | realizing |
| realisation | realization |
| specialise | specialize |
| specialises | specializes |
| specialised | specialized |
| specialising | specializing |
| specialisation | specialization |
| minimise | minimize |
| minimises | minimizes |
| minimised | minimized |
| minimising | minimizing |
| maximise | maximize |
| maximises | maximizes |
| maximised | maximized |
| maximising | maximizing |
| optimise | optimize |
| optimises | optimizes |
| optimised | optimized |
| optimising | optimizing |
| optimisation | optimization |
| optimisations | optimizations |
| utilise | utilize |
| utilises | utilizes |
| utilised | utilized |
| utilising | utilizing |
| utilisation | utilization |
| prioritise | prioritize |
| prioritises | prioritizes |
| prioritised | prioritized |
| prioritising | prioritizing |
| prioritisation | prioritization |
| synchronise | synchronize |
| synchronises | synchronizes |
| synchronised | synchronized |
| synchronising | synchronizing |
| synchronisation | synchronization |
| initialise | initialize |
| initialises | initializes |
| initialised | initialized |
| initialising | initializing |
| initialisation | initialization |
| normalise | normalize |
| normalises | normalizes |
| normalised | normalized |
| normalising | normalizing |
| normalisation | normalization |
| serialise | serialize |
| serialises | serializes |
| serialised | serialized |
| serialising | serializing |
| serialisation | serialization |
| deserialise | deserialize |
| deserialises | deserializes |
| deserialised | deserialized |
| deserialising | deserializing |
| deserialisation | deserialization |
| customise | customize |
| customises | customizes |
| customised | customized |
| customising | customizing |
| customisation | customization |
| standardise | standardize |
| standardises | standardizes |
| standardised | standardized |
| standardising | standardizing |
| standardisation | standardization |
| categorise | categorize |
| categorises | categorizes |
| categorised | categorized |
| categorising | categorizing |
| categorisation | categorization |
| characterise | characterize |
| characterises | characterizes |
| characterised | characterized |
| characterising | characterizing |
| characterisation | characterization |
| summarise | summarize |
| summarises | summarizes |
| summarised | summarized |
| summarising | summarizing |
| summarisation | summarization |
| emphasise | emphasize |
| emphasises | emphasizes |
| emphasised | emphasized |
| emphasising | emphasizing |
| analyse | analyze |
| analyses | analyzes |
| analysed | analyzed |
| analysing | analyzing |
| analyse | analyze |
| paralysed | paralyzed |
-re → -er
| British | American |
|---|
| centre | center |
| centres | centers |
| centred | centered |
| centring | centering |
| fibre | fiber |
| fibres | fibers |
| litre | liter |
| litres | liters |
| lustre | luster |
| metre | meter |
| metres | meters |
| spectre | specter |
| theatre | theater |
| theatres | theaters |
-ce → -se (nouns → verbs)
| British | American |
|---|
| licence | license |
| licences | licenses |
| licenced | licensed |
| practise | practice |
-ll- → -l- (single consonant)
| British | American |
|---|
| labelled | labeled |
| labelling | labeling |
| travelling | traveling |
| travelled | traveled |
| traveller | traveler |
| travellers | travelers |
| cancelled | canceled |
| cancelling | canceling |
| modelled | modeled |
| modelling | modeling |
| signalled | signaled |
| signalling | signaling |
| fulfil | fulfill |
| fulfils | fulfills |
| fulfilled | fulfilled |
| fulfilling | fulfilling |
| fulfilment | fulfillment |
| enrol | enroll |
| enrols | enrolls |
| enrolled | enrolled |
| enrolling | enrolling |
| enrolment | enrollment |
Miscellaneous
| British | American |
|---|
| catalogue | catalog |
| catalogues | catalogs |
| catalogued | cataloged |
| dialogue | dialog |
| dialogues | dialogs |
| programme | program |
| programmes | programs |
| programmed | programmed |
| programming | programming |
| defence | defense |
| defences | defenses |
| offence | offense |
| offences | offenses |
| pretence | pretense |
| pretences | pretenses |
| ageing | aging |
| judgement | judgment |
| judgements | judgments |
| acknowledgement | acknowledgment |
| acknowledgements | acknowledgments |
| colour-blind | color-blind |
| grey | gray |
| greys | grays |
| skilful | skillful |
| skilfully | skillfully |
| mould | mold |
| moulds | molds |
| moulded | molded |
| moulding | molding |
| smoulder | smolder |
| plough | plow |
| ploughs | plows |
| draught | draft |
| draughts | drafts |
| tyre | tire |
| tyres | tires |
| storey | story |
| storeys | stories |
| manoeuvre | maneuver |
| manoeuvres | maneuvers |
| pyjamas | pajamas |
| kerb | curb |
| kerbs | curbs |
| whilst | while |
| amongst | among |
| towards | toward |
5. Apply Edits
Use the Edit tool to make replacements. Prefer a single Edit call per file when possible. If a file has many
scattered replacements, make multiple Edit calls — one per unique replacement site to avoid conflicts.
Never alter:
- The file's indentation or whitespace beyond the changed word
- Code logic, variable names that match package/library identifiers, or locale strings like
en-GB
- URLs, import paths, or dependency names (e.g.
colour in a npm package name)
6. Report Summary
After processing all files, output a markdown summary:
## Americanize Summary
**Target:** `<path>`
**Files scanned:** X
**Files changed:** Y
### Changed Files
| File | Replacements |
|---------------------|-------------------------------------------|
| `path/to/file.md` | colour→color (3), organised→organized (1) |
| `path/to/other.php` | behaviour→behavior (2) |
### No Changes Needed
Files scanned but already using American English (or no British variants found) are not listed here.
If no files needed changes, say so clearly.
Begin now. Read $ARGUMENTS and proceed.