# TreeNodes

> People. Data. Processes.
>
> TreeNodes designs, builds, connects and improves software systems, digital products and applied AI for business operations.

TreeNodes Ltd is a UK-registered software company in London. The work covers systems design, software architecture, custom software and applied AI. Start with Services for the offer, What we build for software capabilities and projects, Applied AI for AI services and the music learning showcase, and Articles for writing and practical examples. How we work explains delivery and engagement options. Company information is on Services; author profiles and writing are in Articles.

Welcome to our public content. The links below lead to Markdown versions generated from the original pages. Each includes its canonical HTML source for citations, full-size visuals and interactive examples. For example, /services/ has a text version at /services/index.md. Our [guide for AI readers](https://treenodes.com/ai-readers/) explains the available formats and browser tools.

## Company and website

- [TreeNodes](https://treenodes.com/index.md): People. Data. Processes. TreeNodes designs, builds, connects and improves software systems, digital products and applied AI for business operations. [HTML source](https://treenodes.com/).
- [Services](https://treenodes.com/services/index.md): Business analysis, technology evaluation, software architecture, web and native app development, APIs and system integrations, data transfer and migration, media, document and data processing, databases, applied AI and scoped technical support. [HTML source](https://treenodes.com/services/).
- [What we do](https://treenodes.com/services/index.md): Applications, business systems, integrations, data, files and media, applied AI, cloud and delivery, and existing software, with the tools TreeNodes uses daily: C# and .NET, JavaScript, Swift, Kotlin, SQL Server, GraphQL, Azure, Google Cloud, Cloudflare, OpenAI and Claude. [HTML source](https://treenodes.com/services/#service-catalogue).
- [Problems we solve](https://treenodes.com/services/index.md): Disconnected tools, data stuck in old systems, manual copying and chasing, files and media to process, legacy systems nobody dares to change, shadow spreadsheets and AI on your own data, each linked to the TreeNodes service that fixes it. [HTML source](https://treenodes.com/services/#problems).
- [How we work](https://treenodes.com/services/working-together/index.md): How a project moves from understanding the business to working software and operation. Compare discovery and scope, architecture review and an initial build, with deliverables, planning ranges, collaboration and handover arrangements. [HTML source](https://treenodes.com/services/working-together/).
- [How TreeNodes works](https://treenodes.com/services/index.md): Your business goes in: people, data, processes and what gets in their way. TreeNodes understands, designs, builds and connects the software, then checks the results in real use and keeps improving it. [HTML source](https://treenodes.com/services/#system-approach).
- [About TreeNodes](https://treenodes.com/services/index.md): Business and systems analysis, technology evaluation, software architecture, hands-on development and applied AI for clearer workflows, connected information and dependable applications. [HTML source](https://treenodes.com/services/#about-treenodes).
- [What we build](https://treenodes.com/products/index.md): Custom web platforms, native apps, APIs and business software. Explore projects in file collection, project management and personalised learning. [HTML source](https://treenodes.com/products/).
- [FileTRX workflow case study](https://treenodes.com/products/filetrx/index.md): A detailed look at the FileTRX request workflow, product design decisions and screenshots, from defining required files to tracking partial completion. [HTML source](https://treenodes.com/products/filetrx/).
- [Projects: platforms, websites and volunteering](https://treenodes.com/case-studies/index.md): Explore TreeNodes platforms, commerce and corporate websites, professional services projects and volunteering, with the delivery scope described for each project. [HTML source](https://treenodes.com/case-studies/).
- [Applied AI](https://treenodes.com/applied-ai/index.md): Business requirements, analysis, architecture, implementation and operation. AI recommendations, document processing, OpenAI, Claude and hosted or self-hosted open-source AI API integration. Showcases a complete music learning platform delivered under NDA in 2023–early 2026 across web, Swift iOS and iPad apps, and Kotlin Android apps. The platform combines data processing, visualisation and course and learner relationships with AI course and learning-path recommendations. Its technology includes C#, GraphQL and an open-source AI API. [HTML source](https://treenodes.com/applied-ai/).
- [Articles](https://treenodes.com/articles/index.md): Browse systems design, applied AI, approach and computer fundamentals. [HTML source](https://treenodes.com/articles/).
- [Article reading paths](https://treenodes.com/articles/reading-paths/index.md): Guided reading on designing an AI system, improving business workflows and making architecture decisions. [HTML source](https://treenodes.com/articles/reading-paths/).
- [Practical resources](https://treenodes.com/resources/index.md): Prompts, code, worksheets and models to try with the articles. [HTML source](https://treenodes.com/resources/).
- [Discuss a project](https://treenodes.com/contact/index.md): Prepare an enquiry, then review and submit it using the contact form. [HTML source](https://treenodes.com/contact/).
- [Search TreeNodes](https://treenodes.com/search/): Find articles, practical resources, services and authors by topic or title.
- [For AI readers](https://treenodes.com/ai-readers/index.md): Read public TreeNodes pages as Markdown, find original sources, and use supported browser tools. [HTML source](https://treenodes.com/ai-readers/).
- [Privacy policy](https://treenodes.com/privacy/index.md): How TreeNodes handles contact enquiries, subscriptions and website data. [HTML source](https://treenodes.com/privacy/).
- [Terms of use](https://treenodes.com/terms/index.md): Terms for using the TreeNodes website, articles and downloadable materials. [HTML source](https://treenodes.com/terms/).
- [Business & systems analysis | TreeNodes services](https://treenodes.com/services/business-systems-analysis/index.md): TreeNodes business and systems analysis: understand workflows, agree requirements and business rules, and define a practical scope for software delivery. [HTML source](https://treenodes.com/services/business-systems-analysis/).
- [Software architecture | TreeNodes services](https://treenodes.com/services/software-architecture/index.md): TreeNodes software architecture: evaluate technology options, system boundaries and dependencies, then agree a workable route for implementation and change. [HTML source](https://treenodes.com/services/software-architecture/).
- [Web, mobile & business software | TreeNodes services](https://treenodes.com/services/software-development/index.md): TreeNodes software development for web and mobile applications, native iOS and Android apps, business systems, APIs, databases and integrations. [HTML source](https://treenodes.com/services/software-development/).
- [Workflow automation | TreeNodes services](https://treenodes.com/services/workflow-automation/index.md): TreeNodes workflow automation: connect business steps, systems and data while keeping approvals, exception handling and operational ownership clear. [HTML source](https://treenodes.com/services/workflow-automation/).
- [Database & technical support | TreeNodes services](https://treenodes.com/services/technical-support/index.md): TreeNodes database and technical support for existing software: investigate issues, maintain data and implement agreed improvements and new requests. [HTML source](https://treenodes.com/services/technical-support/).
- [Designing an AI system](https://treenodes.com/articles/reading-paths/index.md): Choose the parts, define the task, give the agent useful context, then apply it to a changing design. A clearer system design and a task brief you can try with an AI model. [HTML source](https://treenodes.com/articles/reading-paths/#ai-system-design).
- [Improving business workflows](https://treenodes.com/articles/reading-paths/index.md): Understand the work people actually do before changing the software that supports it. A map of hidden rules, responsibilities and exceptions, with a small improvement to test. [HTML source](https://treenodes.com/articles/reading-paths/#work-the-system-cannot-see).
- [Making architecture decisions](https://treenodes.com/articles/reading-paths/index.md): Understand what software architecture means, model the system, choose useful views, then trace what happens at runtime. A design you can explain at several levels, from business rules to a running machine. [HTML source](https://treenodes.com/articles/reading-paths/#dependable-systems-ai-era).
- [Volunteering](https://treenodes.com/case-studies/index.md): Our team has contributed software skills to women’s support, young people’s learning and the arts. These completed projects include a discussion forum, an iOS support app, a volunteer learning platform and a drama school website. For future voluntary work, TreeNodes welcomes enquiries from verified organisations and businesses supporting women living with cancer or widening access to education. We can help with software architecture, applications, websites and databases. We consider each request individually, based on available capacity and where our skills can make a useful contribution. [HTML source](https://treenodes.com/case-studies/#volunteering).

## Articles

- [Skills, MCP, RAG and Memory: How an AI Agent Investigates a 500 Error](https://treenodes.com/articles/skills-mcp-rag-memory-500-error/index.md): A post will not publish. Follow one 500 error from the server logs to a missing database update, and see how skills, MCP, RAG and memory support the investigation. [HTML source](https://treenodes.com/articles/skills-mcp-rag-memory-500-error/). (Applied AI; published 2026-09-22; updated 2026-09-22)
- [Jira and Confluence: From a Business Question to a Working Feature](https://treenodes.com/articles/jira-confluence-business-question-to-working-feature/index.md): Follow the work. Make its logic visible. Three scenarios connect a map of current operations to shared decisions, scoped Jira work and validation. [HTML source](https://treenodes.com/articles/jira-confluence-business-question-to-working-feature/). (Systems design; published 2026-09-16; updated 2026-09-18)
- [What is software architecture?](https://treenodes.com/articles/what-is-software-architecture/index.md): How a system’s parts fit together, why the design matters, and how to think about the choices behind it. [HTML source](https://treenodes.com/articles/what-is-software-architecture/). (Systems design; published 2026-09-09; updated 2026-09-09)
- [If AI can build the software, what is the architect for?](https://treenodes.com/articles/if-ai-can-build-software-what-is-the-architect-for/index.md): A convincing portal demo leaves important decisions open. Follow a delivery-change request to see how architecture connects business rules, system ownership and recovery when AI helps build the software. [HTML source](https://treenodes.com/articles/if-ai-can-build-software-what-is-the-architect-for/). (Systems design; published 2026-09-07; updated 2026-09-07)
- [How AI systems fit together](https://treenodes.com/articles/how-ai-systems-fit-together/index.md): LLMs, RAG, fine-tuning, workflows, agents, MCP and WebMCP: what each contributes, when to use it, and how to combine them in a working system. [HTML source](https://treenodes.com/articles/how-ai-systems-fit-together/). (Applied AI; published 2026-09-06; updated 2026-09-06)
- [What is Astra, and when would I use it?](https://treenodes.com/articles/astra-and-the-moment-the-brief-changes/index.md): Where OpenAI’s Astra fits in architecture and delivery: compare models and pricing, then work through a booking-system migration as the requirements change. [HTML source](https://treenodes.com/articles/astra-and-the-moment-the-brief-changes/). (Applied AI; published 2026-09-05; updated 2026-09-06)
- [The exception path is the real workflow](https://treenodes.com/articles/the-exception-path-is-the-real-workflow/index.md): An invoice needs approval. A reviewer is away. A payment times out. Each needs a different next step. Here is how to design for those cases. [HTML source](https://treenodes.com/articles/the-exception-path-is-the-real-workflow/). (Systems design; published 2026-08-25; updated 2026-09-06)
- [The person missing from the diagram](https://treenodes.com/articles/the-person-missing-from-the-diagram/index.md): The diagram shows a handoff. Someone still has to chase it, check it and make it happen. How to design for the human work your system depends on. [HTML source](https://treenodes.com/articles/the-person-missing-from-the-diagram/). (Systems design; published 2026-08-23; updated 2026-09-06)
- [What the spreadsheet knows that the system does not](https://treenodes.com/articles/what-the-spreadsheet-knows-that-the-system-does-not/index.md): The new system is live. Why does the team still need a spreadsheet? Look at its columns, formulas and workarounds before deciding what to replace. [HTML source](https://treenodes.com/articles/what-the-spreadsheet-knows-that-the-system-does-not/). (Systems design; published 2026-08-23; updated 2026-09-06)
- [What happens when you press a computer’s power button?](https://treenodes.com/articles/what-happens-when-you-press-the-power-button/index.md): From the first light to the login screen: how power, firmware and the operating system bring a computer to life, and where startup can stop. [HTML source](https://treenodes.com/articles/what-happens-when-you-press-the-power-button/). (Computer fundamentals; published 2026-08-22; updated 2026-09-06)
- [The C4 model: architecture at the right level](https://treenodes.com/articles/c4-model-software-architecture/index.md): Explain a software system without putting everything on one diagram. A practical guide to C4 views, examples, AI-assisted documentation and tools. [HTML source](https://treenodes.com/articles/c4-model-software-architecture/). (Systems design; published 2026-08-13; updated 2026-09-06)
- [Give AI agents a design reference](https://treenodes.com/articles/design-references-for-ai-agents/index.md): “Make it look modern” leaves too much to guess. Give your coding agent the colours, type, spacing and component rules it needs to build consistently. [HTML source](https://treenodes.com/articles/design-references-for-ai-agents/). (Applied AI; published 2026-08-10; updated 2026-09-06)
- [Kaizen, applied to software](https://treenodes.com/articles/kaizen-and-software/index.md): A small daily workaround can waste hours over time. How to spot one, try a manageable improvement and check whether it actually helped. [HTML source](https://treenodes.com/articles/kaizen-and-software/). (Approach; published 2026-08-05; updated 2026-09-06)
- [Modelling the system before the code](https://treenodes.com/articles/modelling-the-system-before-the-code/index.md): Sales, Finance and Fulfilment may mean different things by “order”. Find those differences before they become database fields and API rules. [HTML source](https://treenodes.com/articles/modelling-the-system-before-the-code/). (Systems design; published 2026-07-22; updated 2026-09-06)
- [Giving AI a job description](https://treenodes.com/articles/giving-ai-a-job-description/index.md): Before AI reads an invoice or drafts a reply, decide what it should do when it gets stuck. Define the task, the review and the fallback. [HTML source](https://treenodes.com/articles/giving-ai-a-job-description/). (Applied AI; published 2026-06-18; updated 2026-09-06)
- [Software should follow the business](https://treenodes.com/articles/software-should-follow-the-business/index.md): Follow one order, invoice or client request from start to finish. The waits, decisions and workarounds tell you what the software needs to support. [HTML source](https://treenodes.com/articles/software-should-follow-the-business/). (Approach; published 2026-05-12; updated 2026-09-06)

## Authors

- [Nermien Barakat](https://treenodes.com/articles/by/nermien-barakat/index.md): Principal Software Architect & Engineer | Web & Mobile Applications | Business Systems & Applied AI. I design and build web and mobile applications, business systems and applied AI. My work connects how a business operates with the architecture and implementation of its software, from understanding requirements to improving a system in use. [HTML source](https://treenodes.com/articles/by/nermien-barakat/).

## TreeNodes projects

Explore TreeNodes' software and website projects. Each describes its delivery scope and whether support continues; dates refer to its project period. The music learning platform, including its web, iOS, iPad and Android applications, was delivered under NDA by early 2026.

- [FileTRX | TreeNodes projects](https://treenodes.com/case-studies/filetrx/index.md): A product for collecting client files through a structured request, with requirements, outstanding items and progress visible in one place. Analysis, architecture, software implementation and ongoing technical support. Current project [HTML source](https://treenodes.com/case-studies/filetrx/).
- [Infinitely Big | TreeNodes projects](https://treenodes.com/case-studies/infinitely-big/index.md): A complete project management platform connecting projects, client files and file sending, planning and team coordination, with continuing technical support and improvements. Analysis, architecture and frontend and backend development, with ongoing database and technical support, new requirements and implementation. 2008–present [HTML source](https://treenodes.com/case-studies/infinitely-big/).
- [Music learning platform | TreeNodes projects](https://treenodes.com/case-studies/music-learning/index.md): A complete music learning platform across web, iOS, iPad and Android, connecting course information, data processing and visualisation with personalised learning paths and certification. Complete project delivery: requirements analysis, technology evaluation, software architecture, web and native apps, backend, APIs and databases. 2023–early 2026 [HTML source](https://treenodes.com/case-studies/music-learning/).
- [Eyeking Marketplace | TreeNodes projects](https://treenodes.com/case-studies/eyeking/index.md): An eyewear marketplace delivered from the initial idea through analysis, architecture and complete software implementation. Complete project delivery: idea development, requirements analysis, software architecture, frontend and backend implementation. [HTML source](https://treenodes.com/case-studies/eyeking/).
- [2View.COM | TreeNodes projects](https://treenodes.com/case-studies/2view/index.md): A website and backend for a real estate photography and marketing business. Analysis, architecture and complete website and backend development, with continuing technical support. [HTML source](https://treenodes.com/case-studies/2view/).
- [ManUp → Hoottle | TreeNodes projects](https://treenodes.com/case-studies/manup/index.md): A social network for American football fans, connecting member activity, conversations and shared interests. ManUp developed into Hoottle. Analysis, architecture and complete frontend and backend development, with continuing technical support. From 2009 · Three-year project [HTML source](https://treenodes.com/case-studies/manup/).
- [MIDI | TreeNodes projects](https://treenodes.com/case-studies/midi/index.md): An interactive Case Studies section for a product development website, connecting category browsing with project details and imagery. Frontend implementation of the Case Studies section using HTML, CSS and jQuery. [HTML source](https://treenodes.com/case-studies/midi/).
- [MedImmune | TreeNodes projects](https://treenodes.com/case-studies/medimmune/index.md): A corporate website project delivered from the initial idea through analysis, architecture and complete implementation. Complete website project delivery: idea development, requirements analysis, software architecture and implementation. [HTML source](https://treenodes.com/case-studies/medimmune/).
- [Eliquis e-library | TreeNodes projects](https://treenodes.com/case-studies/eliquis/index.md): A resource portal connecting category navigation with document and media discovery. Website and resource-library development, including category navigation, document and media browsing. [HTML source](https://treenodes.com/case-studies/eliquis/).
- [Capital Contractors | TreeNodes projects](https://treenodes.com/case-studies/capital-contractors/index.md): A facilities-services website delivered from the initial idea through analysis, architecture and complete implementation. Complete website project delivery: idea development, requirements analysis, software architecture and implementation. [HTML source](https://treenodes.com/case-studies/capital-contractors/).
- [Mavrides Moyal & Associates | TreeNodes projects](https://treenodes.com/case-studies/mavrides-moyal/index.md): A public website for a legal practice, delivered from the initial idea through analysis, architecture and complete implementation. Complete website project delivery: idea development, requirements analysis, software architecture and implementation. [HTML source](https://treenodes.com/case-studies/mavrides-moyal/).
- [Women’s discussion forum | TreeNodes projects](https://treenodes.com/case-studies/women-living-with-cancer/index.md): A women’s community discussion website, delivered through requirements analysis, website and data structure, and software implementation. Requirements analysis, architecture, website and database implementation, with attention to sensitive information. [HTML source](https://treenodes.com/case-studies/women-living-with-cancer/).
- [Women’s support app | TreeNodes projects](https://treenodes.com/case-studies/womens-support-app/index.md): A completed iOS app bringing daily records, chemotherapy and medication planning, diary entries and trend charts together. Complete project delivery: requirements, architecture, frontend, backend, APIs and databases. [HTML source](https://treenodes.com/case-studies/womens-support-app/).
- [Volunteer learning platform | TreeNodes projects](https://treenodes.com/case-studies/learning-support/index.md): A platform connecting young people aged 11–17 with verified volunteer teachers and university students for supervised, recorded online classes. Website analysis, architecture and software contribution for learning resources and volunteer connections. [HTML source](https://treenodes.com/case-studies/learning-support/).
- [Drama school website | TreeNodes projects](https://treenodes.com/case-studies/drama-school/index.md): A completed WordPress website helping a drama school present its classes online. Website development and class presentation using WordPress. [HTML source](https://treenodes.com/case-studies/drama-school/).

## Reader exercises and downloads

Each exercise includes instructions and expected results in its article. Supplied fictional records and illustrative outputs are identified there.

- [Diagnose the publishing failure](https://treenodes.com/articles/skills-mcp-rag-memory-500-error/index.md): Use a small, fictional evidence pack to check whether an explanation follows from the records. [HTML source](https://treenodes.com/articles/skills-mcp-rag-memory-500-error/#reader-exercise).
  - [Trace a 500 error from the evidence](https://treenodes.com/downloads/practice/ai-agent-500-error-evidence.txt)
- [Can a colleague follow the change?](https://treenodes.com/articles/jira-confluence-business-question-to-working-feature/index.md): Pick one requirement that changed recently. Give a colleague its Jira story and ask them to find the reason, decision owner, impacted work and validation evidence. [HTML source](https://treenodes.com/articles/jira-confluence-business-question-to-working-feature/#reader-exercise).
  - [Decision-to-delivery worksheet](https://treenodes.com/downloads/practice/decision-to-delivery-worksheet.txt)
- [Try it in five minutes](https://treenodes.com/articles/what-is-software-architecture/index.md): Identify the parts, responsibilities and connections in a fictional shared task application. [HTML source](https://treenodes.com/articles/what-is-software-architecture/#reader-exercise).
  - [Explain a small system](https://treenodes.com/downloads/practice/software-architecture-promise-review.txt)
- [Recover an uncertain delivery change](https://treenodes.com/articles/if-ai-can-build-software-what-is-the-architect-for/index.md): Use the article’s hypothetical supplier and a delivery-change request whose response never arrived. Compare the proposed customer state and recovery process with the business rules. [HTML source](https://treenodes.com/articles/if-ai-can-build-software-what-is-the-architect-for/#reader-exercise).
  - [Recover a delivery-change request](https://treenodes.com/downloads/practice/delivery-change-recovery.txt)
- [Review a supplier using supplied evidence](https://treenodes.com/articles/how-ai-systems-fit-together/index.md): Two prompts, fictional supplier evidence, a review policy and expected outcomes. [HTML source](https://treenodes.com/articles/how-ai-systems-fit-together/#try-it-yourself).
  - [Both supplier-review prompts](https://treenodes.com/downloads/supplier-review-prompts.txt)
- [Design the booking migration](https://treenodes.com/articles/astra-and-the-moment-the-brief-changes/index.md): Use the same four-location business and the same launch constraint. First plan the staged migration; then add customer credits that must work across locations. [HTML source](https://treenodes.com/articles/astra-and-the-moment-the-brief-changes/#reader-exercise).
  - [1. Prepare the migration decision](https://treenodes.com/downloads/practice/booking-migration-brief.txt)
  - [2. Introduce shared credits](https://treenodes.com/downloads/practice/booking-credit-change.txt)
- [Make an uncertain payment recoverable](https://treenodes.com/articles/the-exception-path-is-the-real-workflow/index.md): A timeout leaves the payment outcome unknown. This small state machine makes the next action explicit and keeps a repeated event from changing the case twice. [HTML source](https://treenodes.com/articles/the-exception-path-is-the-real-workflow/#reader-exercise).
  - [Payment state and event handling](https://treenodes.com/downloads/practice/exception-transitions.mjs)
- [Review a handoff before automating it](https://treenodes.com/articles/the-person-missing-from-the-diagram/index.md): Use a handoff review to find the responsibility hidden inside an arrow. The useful result is an agreement about the work, including what happens when the usual person is away. [HTML source](https://treenodes.com/articles/the-person-missing-from-the-diagram/#reader-exercise).
  - [Handoff review worksheet](https://treenodes.com/downloads/practice/handoff-review.txt)
- [Recover the rules behind a spreadsheet](https://treenodes.com/articles/what-the-spreadsheet-knows-that-the-system-does-not/index.md): A table alone will not explain why somebody highlighted a row. Use the records and their accompanying notes to separate an observed workaround from an agreed business rule. [HTML source](https://treenodes.com/articles/what-the-spreadsheet-knows-that-the-system-does-not/#reader-exercise).
  - [Sample request register](https://treenodes.com/downloads/practice/request-register.csv)
  - [Extract candidate rules with evidence](https://treenodes.com/downloads/practice/spreadsheet-rule-review.txt)
- [Inspect your own startup](https://treenodes.com/articles/what-happens-when-you-press-the-power-button/index.md): The layers in the article leave different evidence. These read-only commands show either startup timing or the operating system’s recorded boot time; those are different measurements. [HTML source](https://treenodes.com/articles/what-happens-when-you-press-the-power-button/#reader-exercise).
  - [Linux using systemd: startup timing](https://treenodes.com/downloads/practice/startup-linux.sh)
  - [macOS: recorded boot time and uptime](https://treenodes.com/downloads/practice/startup-macos.sh)
  - [Windows PowerShell: recorded OS boot time](https://treenodes.com/downloads/practice/startup-windows.ps1)
- [Generate two views from one model](https://treenodes.com/articles/c4-model-software-architecture/index.md): The Business Operations Platform in this article can be represented as one maintained model. This example generates its context and container views without drawing the same relationship twice. [HTML source](https://treenodes.com/articles/c4-model-software-architecture/#reader-exercise).
  - [Business Operations Platform model](https://treenodes.com/downloads/practice/workspace.dsl)
  - [Compare the model with repository evidence](https://treenodes.com/downloads/practice/c4-evidence-review.txt)
- [Build from a design reference](https://treenodes.com/articles/design-references-for-ai-agents/index.md): Give the agent a screen with a defined job. This reference turns the supplier-review example into a small implementation task while leaving the existing project’s visual identity intact. [HTML source](https://treenodes.com/articles/design-references-for-ai-agents/#reader-exercise).
  - [The design reference](https://treenodes.com/downloads/practice/DESIGN.md)
  - [The implementation brief](https://treenodes.com/downloads/practice/design-implementation-brief.txt)
- [Define one improvement worth keeping](https://treenodes.com/articles/kaizen-and-software/index.md): Keep the experiment smaller than the problem. This worksheet makes the benefit and the cost visible before a small change becomes a permanent dependency. [HTML source](https://treenodes.com/articles/kaizen-and-software/#reader-exercise).
  - [One-week improvement experiment](https://treenodes.com/downloads/practice/kaizen-experiment.txt)
- [Resolve three meanings of “confirmed”](https://treenodes.com/articles/modelling-the-system-before-the-code/index.md): Start with the disagreement in the article. The aim is to preserve each department’s facts while exposing the decision that crosses their boundaries. [HTML source](https://treenodes.com/articles/modelling-the-system-before-the-code/#reader-exercise).
  - [Order modelling brief](https://treenodes.com/downloads/practice/order-modelling-brief.txt)
- [Give invoice extraction a contract](https://treenodes.com/articles/giving-ai-a-job-description/index.md): The useful output is an evidence-backed record that a reviewer can use. This exercise makes missing information and unreadable documents explicit without granting payment authority. [HTML source](https://treenodes.com/articles/giving-ai-a-job-description/#reader-exercise).
  - [Invoice extraction task](https://treenodes.com/downloads/practice/invoice-task-contract.txt)
  - [Schema for one returned record](https://treenodes.com/downloads/practice/invoice-record.schema.json)
- [Turn a file-request process into a discovery brief](https://treenodes.com/articles/software-should-follow-the-business/index.md): Before choosing screens or services, identify the commitments the software has to support. This uses the client-file request from the article. [HTML source](https://treenodes.com/articles/software-should-follow-the-business/#reader-exercise).
  - [Discovery and capability brief](https://treenodes.com/downloads/practice/file-request-discovery.txt)

## Discovery and supported browser actions

- [Public content catalogue](https://treenodes.com/content-index.json): machine-readable metadata for the pages, articles and resources above.
- [XML sitemap](https://treenodes.com/sitemap-index.xml): canonical pages intended for indexing. Internal search and demonstration pages are excluded.
- [Search TreeNodes](https://treenodes.com/search/): search the same public catalogue by topic, title, author or resource type.
- In compatible browsers, WebMCP exposes treenodes_find_content and treenodes_open_page. The contact page also exposes treenodes_prepare_contact, which prepares a visible draft for the visitor to review and send. It never submits the enquiry.
- This text file and the content catalogue are optional discovery aids. Neither is an MCP server or a WebMCP protocol endpoint. Browser support and search-engine inclusion are outside the site's control.

## Attribution

Link to the specific article or exercise when citing it. TreeNodes refers to this company, not unrelated projects with the same name. Use the author name supplied with an article, and distinguish supplied examples from reported production work.