# AGENTS.md — Build guide for Loco

## Project scope
Edit translation keys in a locale matrix, preserve context and plural forms, import a chosen format and export reviewed strings.

Catalogue verdict: kinda. The core of Loco is a keyed string store with a locale matrix on top, and that part is genuinely a one-sitting build: SQLite, a table view, an import and an export. What eats the weekend is the format layer, because gettext PO with plural headers, Apple .strings and .stringsdict, Android plurals XML, ICU messages and flat JSON all disagree about pluralization and escaping in ways that only show up in production. Machine translation fill-in is a single API call if you already have a DeepL or provider key. If you are the only translator, a local build is fine and arguably faster to work with. If you send links to freelance translators and rely on the hosted API in CI, you are rebuilding a service, not a tool.
Use the implementation prompt below to define the deliverable. Complete each phase's acceptance checks before extending the scope.

## Working agreement
- Inspect the repository and its existing instructions before choosing paths, dependencies or commands. Keep one coherent stack and explain changes to the proposed architecture.
- Plan a vertical slice that accepts a real input and produces the useful output described below. Persist only the state the prompt calls for; respect memory-only and upstream-managed workflows. Use fixtures only when they are clearly labelled.
- After scaffolding, document the actual install, development, check and build commands in README and keep them synchronized with the package or project manifest. Do not report commands as successful unless they ran.
- Work in small steps. At handoff, list implemented flows, checks actually performed, remaining blockers, and any credentials or provider setup the owner must supply.
- Do not publish, spend money, contact customers, delete source data or run irreversible migrations without the project owner's authorization.

## Prerequisites
- Runtime and tools: TypeScript, React and a Node server with SQLite for a single small workspace.
- Before starting: A local Node runtime, writable data directory, sample records and a documented backup/restore path.

## Stack and architecture
- TypeScript, React and a Node server with SQLite for a single small workspace
- Data design: Store Project, Key, Locale, TranslationRevision and PlaceholderSet; every translated string preserves required interpolation tokens and retains empty/untranslated status explicitly.
- Setup: A local Node runtime, writable data directory, sample records and a documented backup/restore path

## Security and data integrity
- Use migrations and server-side validation; expose saved, pending and failed states. Keep each write atomic and reject stale edits using a revision number.
- Choose JSON plus one documented PO dialect initially. Plurals and nested key structures are format-specific; do not claim universal lossless conversion or auto-publish machine translations.
- Keep secrets outside client bundles and exported projects; document what leaves the device and make retention/deletion controls visible.

## Agent implementation rules
- Project rule — domain: Store Project, Key, Locale, TranslationRevision and PlaceholderSet; every translated string preserves required interpolation tokens and retains empty/untranslated status explicitly.
- Project rule — scope and recovery: Choose JSON plus one documented PO dialect initially. Plurals and nested key structures are format-specific; do not claim universal lossless conversion or auto-publish machine translations.
- Project rule — acceptance: Translate a string containing {count} and an escaped newline, omit the token once and export; reject the invalid translation and round-trip the valid escapes unchanged.
- Project rule — delivery: document real setup commands and permissions; do not claim a build, accuracy level, performance result or security certification that has not been demonstrated.

## Optional agent skills and references
- Recommended skill: [vercel-react-best-practices](https://github.com/vercel-labs/agent-skills/blob/main/skills/react-best-practices/SKILL.md) — keep the proposed React work/review views responsive and avoid unnecessary rendering or data-fetch waterfalls. Follow the maintainer's installation instructions and match its requirements to the chosen runtime.
- Recommended skill: [web-design-guidelines](https://github.com/vercel-labs/agent-skills/blob/main/skills/web-design-guidelines/SKILL.md) — review keyboard access, focus, validation, error recovery and the readable work/review interface or HTML report. Follow the maintainer's installation instructions and match its requirements to the chosen runtime.

Read the linked SKILL.md and its dependencies before adding a skill. Select only the skills matching this project's runtime and task; their documentation does not supply API access, credentials or approval to perform external actions. Pin the reviewed revision where the tool supports it. Follow the chosen agent's documented project-level installation mechanism.

## Distribution ideas
These are optional planning notes. Obtain the owner's approval before publishing or contacting anyone.
- Demonstrate this working slice using synthetic or explicitly authorized non-sensitive examples: Edit translation keys in a locale matrix, preserve context and plural forms, import a chosen format and export reviewed strings.
- Share a synthetic example export and the acceptance walkthrough; keep real customer, health, financial and source data private: Translate a string containing {count} and an escaped newline, omit the token once and export; reject the invalid translation and round-trip the valid escapes unchanged.
- State the limits before asking someone to replace their existing tool: Choose JSON plus one documented PO dialect initially. Plurals and nested key structures are format-specific; do not claim universal lossless conversion or auto-publish machine translations.

## Engineering roadmap
1. Phase 1 — Pin the working slice and create its example input: Edit translation keys in a locale matrix, preserve context and plural forms, import a chosen format and export reviewed strings. Confirm setup: A local Node runtime, writable data directory, sample records and a documented backup/restore path.
2. Phase 2 — Implement persistence and write-time invariants before decorating the UI: Store Project, Key, Locale, TranslationRevision and PlaceholderSet; every translated string preserves required interpolation tokens and retains empty/untranslated status explicitly.
3. Phase 3 — Connect the working view to real saved state. Use migrations and server-side validation; expose saved, pending and failed states. Keep each write atomic and reject stale edits using a revision number.
4. Phase 4 — Expose the app-specific limits and recovery path in context: Choose JSON plus one documented PO dialect initially. Plurals and nested key structures are format-specific; do not claim universal lossless conversion or auto-publish machine translations.
5. Phase 5 — Walk through this concrete acceptance case and preserve its exported evidence: Translate a string containing {count} and an escaped newline, omit the token once and export; reject the invalid translation and round-trip the valid escapes unchanged. Finish the README and backup/restore instructions; report unfinished capabilities explicitly.

## Paid-product capabilities outside this build
- Format breadth: Loco reads and writes a long tail of formats, including the awkward Apple and Qt ones, with plural rules per locale already correct
- A shareable editor for non-technical translators, with roles, comments and progress tracking
- A stable public API and CLI that CI pipelines can pull from at build time
- Translation history, who changed what, and the ability to roll a string back
- Glossary and translation memory suggestions that improve as the project grows

## Implementation prompt
Build the following focused alternative to Loco. This is a deliberately limited personal or small-team substitute, not parity with the paid service.

WORKING SLICE
Edit translation keys in a locale matrix, preserve context and plural forms, import a chosen format and export reviewed strings.

SETUP AND ARCHITECTURE
Use TypeScript, React and a Node server with SQLite for a single small workspace. Prerequisites: A local Node runtime, writable data directory, sample records and a documented backup/restore path. Before integrating anything, record actual versions and permissions, plus model files or provider limits only where used, in the README; make unavailable dependencies visible rather than simulating success.

DOMAIN MODEL AND INVARIANTS
Store Project, Key, Locale, TranslationRevision and PlaceholderSet; every translated string preserves required interpolation tokens and retains empty/untranslated status explicitly.

IMPLEMENTATION CONTRACT
Use migrations and server-side validation; expose saved, pending and failed states. Keep each write atomic and reject stale edits using a revision number. Provide an input/setup view, the main work view, and a review/export view appropriate to this workflow. Preserve the last saved state if a job or save fails. Include empty, loading, permission-denied, partial and retryable-error states. Log identifiers and error categories without secret values or unnecessary private content.

APP-SPECIFIC BOUNDARY AND RECOVERY
Choose JSON plus one documented PO dialect initially. Plurals and nested key structures are format-specific; do not claim universal lossless conversion or auto-publish machine translations.

ACCEPTANCE SCENARIO
Translate a string containing {count} and an escaped newline, omit the token once and export; reject the invalid translation and round-trip the valid escapes unchanged. Also reopen the app after an interrupted operation, confirm the saved record/export remains inspectable, and document the recovery action. These are implementation acceptance requirements, not a claim that this guide has been tested.

DELIVERY
Deliver a runnable repository with migrations or project-format versioning, a non-sensitive example, environment/permission setup, the exact manual acceptance steps, and a backup/export-and-restore walkthrough. Implement the working slice before optional integrations; list any deferred paid-product capabilities honestly. Do not add capabilities outside the working slice just to resemble the original product.

PROJECT RULES FOR AGENTS.md
Keep the domain invariants above executable at the write boundary. Propose scope changes before adding providers or permissions. Never fabricate source evidence, publish results, identity matches or successful delivery. Preserve user originals and require an explicit confirmation for destructive changes or external publication.

## Completion evidence
Demonstrate the prompt's acceptance scenarios against the scoped workflow. Include setup from a clean checkout and failure recovery. Check persistence across restart and export/restore only for the state the prompt says to store; for memory-only tools, confirm that temporary content is discarded as specified. Record actual results and remaining limitations. A detailed plan alone does not establish a working replacement.