# AGENTS.md — Build guide for Tallymeter ## Project scope Start a timer against a project, review/edit descriptions and roll approved uninvoiced time into a numbered PDF invoice. Keep a manual paid status and export an audit of included entries. Catalogue verdict: kinda. The solo core is a weekend build and nobody should pretend otherwise: a timer, projects with hourly rates, and uninvoiced hours rolled into a numbered PDF. What survives the rebuild is the boring half · two-way Jira worklog sync that reconciles ticket by ticket without double-counting, a hosted MCP server and scoped API tokens your agents can reach from any machine, and invoice numbering plus VAT and bank details that hold up when an accountant reads them. Full disclosure: this entry was submitted by the person who builds Tallymeter. Same rubric as everything else on the list, and the honest answer is that a freelancer billing one client can absolutely one-shot the part they use. 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 - Do not publish, spend money, contact customers, delete source data or run irreversible migrations without the project owner's authorization.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 - A supported Node release, a writable local data directory and a separate backup location. Bind to localhost; remote use requires authentication and HTTPS first. - Implementation components: Node.js, TypeScript and Express with server-rendered HTML and small browser modules. SQLite through better-sqlite3 with migrations, prepared statements and a single background worker. - Scope boundary: Tax advice and automatic collection are outside scope. ## Stack and architecture - Node.js, TypeScript and Express with server-rendered HTML and small browser modules. - SQLite through better-sqlite3 with migrations, prepared statements and a single background worker. - Domain model: clients, projects, running timers, corrected time entries, rate snapshots and sequential invoice records ## Security and data integrity - Reject unexpected origins and unbounded request bodies even on localhost. Keep credentials outside the database export and redact sensitive text from logs. - Correctness boundary: At most one timer is running per user; issued invoices freeze rates and time totals and no entry is invoiced twice. - Use short SQLite transactions and persist job state before starting work. Give retries stable operation IDs; report incomplete or unknown results instead of silently repeating them. - Use a consistent SQLite backup and an attachment manifest. Export portable JSON/CSV, then restore to a new directory without overwriting the original data. ## Agent implementation rules - Project rule — data model: clients, projects, running timers, corrected time entries, rate snapshots and sequential invoice records - Project rule — preserve this invariant: At most one timer is running per user; issued invoices freeze rates and time totals and no entry is invoiced twice. - Project rule — acceptance evidence: Restart while a timer is active and recover its start time; generating two invoices concurrently cannot reuse a time entry or invoice number. ## Optional agent skills and references - Optional external skill: [web-design-guidelines](https://github.com/vercel-labs/agent-skills/blob/main/skills/web-design-guidelines/SKILL.md) — Review web interfaces for accessibility, keyboard focus, forms, navigation and interaction quality. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission. - Optional external skill: [sharp-edges](https://github.com/trailofbits/skills/blob/main/plugins/sharp-edges/skills/sharp-edges/SKILL.md) — Review security-sensitive APIs and configuration for dangerous defaults and easy-to-misuse interfaces. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission. - Optional external skill: [pdf](https://github.com/anthropics/skills/blob/main/skills/pdf/SKILL.md) — Process PDFs through extraction, generation, page operations, form filling and OCR workflows. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission. 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 the actual Tallymeter-inspired workflow with owned or clearly labeled sample data: Start a timer against a project, review/edit descriptions and roll approved uninvoiced time into a numbered PDF invoice. Keep a manual paid status and export an audit of included entries. - Publish a reproducible walkthrough with this observable result: Restart while a timer is active and recover its start time; generating two invoices concurrently cannot reuse a time entry or invoice number. - Explain who can operate this scoped tool, its setup and ongoing costs, and these remaining product gaps: Tax advice and automatic collection are outside scope. Avoid guaranteed savings, performance scores or implied endorsement. ## Engineering roadmap 1. Phase 1 — Scope and fixtures. Implement this bounded workflow: Start a timer against a project, review/edit descriptions and roll approved uninvoiced time into a numbered PDF invoice. Keep a manual paid status and export an audit of included entries. Record prerequisites, select representative user-owned fixtures and document the unsupported features: Tax advice and automatic collection are outside scope. 2. Phase 2 — Durable model. Model clients, projects, running timers, corrected time entries, rate snapshots and sequential invoice records Add migrations or a versioned document format, explicit validation, stable IDs and a visible import-error report. Preserve this rule: At most one timer is running per user; issued invoices freeze rates and time totals and no entry is invoiced twice. 3. Phase 3 — Complete the first useful path. Implement the workflow's input, review and output interface, with clear controls and explicit empty/error states. Use short SQLite transactions and persist job state before starting work. Give retries stable operation IDs; report incomplete or unknown results instead of silently repeating them. 4. Phase 4 — Permissions and integration failure. Reject unexpected origins and unbounded request bodies even on localhost. Keep credentials outside the database export and redact sensitive text from logs. Request integration credentials and permissions only for the enabled feature; show a disconnected state instead of mock results. 5. Phase 5 — Portable handoff. Use a consistent SQLite backup and an attachment manifest. Export portable JSON/CSV, then restore to a new directory without overwriting the original data. Include setup, operating limits, fixture walkthrough and shutdown/restart instructions in the README. 6. Phase 6 — Acceptance scenarios. Restart while a timer is active and recover its start time; generating two invoices concurrently cannot reuse a time entry or invoice number. Repeat the workflow after restart and with a denied permission or unavailable dependency; show recoverable failure rather than a success placeholder. ## Paid-product capabilities outside this build - two-way Jira Cloud worklog sync that reconciles ticket by ticket - a hosted MCP server and scoped API tokens agents can call from anywhere, with per-agent attribution - invoice numbering, VAT and bank details that survive an accountant handoff - shared team workspaces and per-member unbilled totals - managed hosting, nightly backups and a phone-sized UI for starting a timer away from your desk ## Implementation prompt WORKING SLICE Start a timer against a project, review/edit descriptions and roll approved uninvoiced time into a numbered PDF invoice. Keep a manual paid status and export an audit of included entries. Build this scoped Tallymeter-inspired workflow with a documented data model and visible failure states. Architecture - Node.js, TypeScript and Express with server-rendered HTML and small browser modules. - SQLite through better-sqlite3 with migrations, prepared statements and a single background worker. Prerequisites and limits A supported Node release, a writable local data directory and a separate backup location. Bind to localhost; remote use requires authentication and HTTPS first. Outside this release: Tax advice and automatic collection are outside scope. Data model and correctness clients, projects, running timers, corrected time entries, rate snapshots and sequential invoice records Invariant: At most one timer is running per user; issued invoices freeze rates and time totals and no entry is invoiced twice. Use short SQLite transactions and persist job state before starting work. Give retries stable operation IDs; report incomplete or unknown results instead of silently repeating them. Security and privacy Reject unexpected origins and unbounded request bodies even on localhost. Keep credentials outside the database export and redact sensitive text from logs. Recovery and export Use a consistent SQLite backup and an attachment manifest. Export portable JSON/CSV, then restore to a new directory without overwriting the original data. Implementation order 1. Phase 1 — Scope and fixtures. Implement this bounded workflow: Start a timer against a project, review/edit descriptions and roll approved uninvoiced time into a numbered PDF invoice. Keep a manual paid status and export an audit of included entries. Record prerequisites, select representative user-owned fixtures and document the unsupported features: Tax advice and automatic collection are outside scope. 2. Phase 2 — Durable model. Model clients, projects, running timers, corrected time entries, rate snapshots and sequential invoice records Add migrations or a versioned document format, explicit validation, stable IDs and a visible import-error report. Preserve this rule: At most one timer is running per user; issued invoices freeze rates and time totals and no entry is invoiced twice. 3. Phase 3 — Complete the first useful path. Implement the workflow's input, review and output interface, with clear controls and explicit empty/error states. Use short SQLite transactions and persist job state before starting work. Give retries stable operation IDs; report incomplete or unknown results instead of silently repeating them. 4. Phase 4 — Permissions and integration failure. Reject unexpected origins and unbounded request bodies even on localhost. Keep credentials outside the database export and redact sensitive text from logs. Request integration credentials and permissions only for the enabled feature; show a disconnected state instead of mock results. 5. Phase 5 — Portable handoff. Use a consistent SQLite backup and an attachment manifest. Export portable JSON/CSV, then restore to a new directory without overwriting the original data. Include setup, operating limits, fixture walkthrough and shutdown/restart instructions in the README. 6. Phase 6 — Acceptance scenarios. Restart while a timer is active and recover its start time; generating two invoices concurrently cannot reuse a time entry or invoice number. Repeat the workflow after restart and with a denied permission or unavailable dependency; show recoverable failure rather than a success placeholder. Acceptance Restart while a timer is active and recover its start time; generating two invoices concurrently cannot reuse a time entry or invoice number. Use real source data or clearly labeled fixtures. Explain unsupported input and provider failures; do not fabricate analytics, delivery receipts, accuracy claims or security guarantees. Optional agent guidance Optional external skill: [web-design-guidelines](https://github.com/vercel-labs/agent-skills/blob/main/skills/web-design-guidelines/SKILL.md) — Review web interfaces for accessibility, keyboard focus, forms, navigation and interaction quality. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission. Optional external skill: [sharp-edges](https://github.com/trailofbits/skills/blob/main/plugins/sharp-edges/skills/sharp-edges/SKILL.md) — Review security-sensitive APIs and configuration for dangerous defaults and easy-to-misuse interfaces. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission. Optional external skill: [pdf](https://github.com/anthropics/skills/blob/main/skills/pdf/SKILL.md) — Process PDFs through extraction, generation, page operations, form filling and OCR workflows. Review its instructions and compatibility before use; it does not grant deployment, data-access or publication permission. Project rule — data model: clients, projects, running timers, corrected time entries, rate snapshots and sequential invoice records Project rule — preserve this invariant: At most one timer is running per user; issued invoices freeze rates and time totals and no entry is invoiced twice. Project rule — acceptance evidence: Restart while a timer is active and recover its start time; generating two invoices concurrently cannot reuse a time entry or invoice number. ## 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.