Hub / Design Docs

Design Document Library

Engineering documents published as pages rather than PDFs, so they can be linked to a line, read on a phone, and corrected without reissuing a file. The library is new — these are the first entries, and the conventions below are what the next one should follow.

Numbered specs 2 Architecture pages 3 Format HTML, versioned in git

Specifications

Numbered Documents

Architecture & assessment

Longer-Form Engineering Pages

Not numbered, because they describe a specific connector rather than specifying platform-wide behaviour — but they belong to the same library and are written to the same standard.

Authoring

Writing One

Copy the template, keep the section numbering, and change nothing about the styling.

Open the template →
Step 1

Copy the template file

Duplicate tsanet-design-doc-template.html and rename it tsanet-2026-NNN-short-slug.html. It links hub.css and doc.css and defines no colours of its own — leave it that way, so a brand change lands everywhere at once.

Step 2

Fill the masthead honestly

The Verified against cell is the one that matters: name what you actually checked. "The OpenAPI specification" and "a live call on Beta" are useful; "internal knowledge" means the reader should not trust the numbers.

Step 3

Use callouts sparingly

Note for a convention worth pulling out of the flow, Constraint for something that will bite. Not for emphasis in general — a page where everything is highlighted highlights nothing.

Step 4

Draw with the shared primitives

Inline SVG using .bx, .ln, .tt, .ts, .tl from hub.css rather than literal colours. Give each figure a caption that says what to take from it, not what it depicts.

Conventions

Numbering, Status and What Belongs Here

ConventionDetail
Document numberTSANET-YYYY-NNN, allocated in sequence within the year. The number never changes, including when the document is superseded.
StatusDRAFT while it can still move, APPROVED once ratified, SUPERSEDED when a later document replaces it. A superseded document stays published and links forward.
VersionIndependent of status. Bump it for any substantive change and add a revision-history row saying what moved.
Cross-referencesBy number and hyperlink. Every document in this library is a page, so a reference that does not link is a reference the reader has to hunt for.

What belongs in this library

  • Platform-wide behaviour that more than one connector has to implement the same way.
  • Contracts and models — the shape of a thing, and the consequences of that shape.
  • Assessments of a platform before anything is built, with claims tagged by evidence level.
  • Not endpoint reference — that is generated from the specification and lives in GitBook.
  • Not setup runbooks for one connector — those belong on the connector page.
  • Not internal decision papers. If a document is classified internal, the publishable half is usually a different document.
One standard applies to everything here: verify against the source rather than writing from memory, and say in the document what you verified against. Where two sources disagree, say so on the page instead of quietly picking one — a documented contradiction is more useful to the reader than a confident guess.