Documentation, Examples, and Executable API Promises¶

Page Maps¶

graph LR
  family["Python Programming"]
  program["Python Object-Oriented Programming"]
  section["Public Apis Extension Governance"]
  page["Documentation, Examples, and Executable API Promises"]
  capstone["Capstone evidence"]

  family --> program --> section --> page
  page -.applies in.-> capstone

flowchart LR
  orient["Orient on the page map"] --> read["Read the main claim and examples"]
  read --> inspect["Inspect the related code, proof, or capstone surface"]
  inspect --> verify["Run or review the verification path"]
  verify --> apply["Apply the idea back to the module and capstone"]

This lesson is about a simple but costly truth:

for many users, the documentation is the API

They learn what is supported from:

the first quickstart they copy
the first import path they see
the first configuration example they trust
the first migration note they need under pressure

If those surfaces teach the wrong path, the wrong path is effectively public whether the maintainers intended that or not.

Keep one public story visible¶

Use the capstone package:

service_monitoring

Assume the supported story is:

import the package facade
configure one supported sink seam if needed
run the workflow
handle the documented outcome surface

Now ask:

would a new learner who reads the docs today be taught exactly that story, or would they still learn internal shortcuts?

That is the real documentation-governance test.

Examples are support promises in executable clothing¶

Examples do more than explain syntax. They silently answer:

which import path is sanctioned
which arguments matter
which failures a caller should expect
which extension seam is actually intended

That means a deep internal import in a quickstart is not a harmless shortcut. It is a public promise with no governance around it.

This is why example review belongs in API governance, not only in copy editing.

Different docs have different jobs¶

Keep the roles explicit:

tutorials teach first use and narrative flow
how-to guides solve one focused task
reference pages define stable inputs, outputs, and guarantees
explanation pages teach tradeoffs and reasoning

When those roles blur, readers cannot tell:

what is the supported contract
what is only narrative scaffolding
what is safe to depend on long-term

Public-doc discipline starts with role discipline.

The first copied example matters most¶

If the first example a learner copies imports:

runtime workers
repository wiring
adapter helpers

then those internals have already become the accidental API.

That is why the highest-value examples should use:

the supported facade
the supported extension seam
realistic configuration
realistic failure handling

Examples are part of governance, not garnish.

Important examples should be executable¶

Important public examples should fail when the supported surface drifts.

That may mean:

a smoke-tested quickstart
checked snippets
a sample command path exercised in CI
a compatibility packet that mirrors the docs

The goal is not to execute every paragraph. The goal is to keep the most important public stories from fossilizing.

If the example is valuable enough to teach the API, it is valuable enough to protect.

Failure-path docs belong in the contract too¶

Weak API documentation teaches only the success path.

A stronger public story also documents:

what configuration errors look like
what unsupported inputs are rejected early
what deprecation or migration path callers should follow
what extension limits the host enforces

Otherwise the docs teach the system only in its easiest mood and leave users to discover the real boundary behavior by failure.

Worked capstone document set¶

An honest public document set for this package could include:

one quickstart using only service_monitoring facade imports
one short extension example showing IncidentSink in the supported role
one reference page defining stable inputs, outcomes, and failure meanings
one migration note when public names or shapes change
one executable route that keeps the main quickstart honest

What it should not include:

deep runtime imports because they are shorter
examples that bypass supported construction
stale snippets teaching a deprecated path as though it were current on Monday, July 27, 2026

Docs and compatibility must move together¶

When a public surface changes, update all of these together:

reference page
quickstart
executable examples
migration guidance
compatibility or review route

If code changes first and docs catch up later, users receive conflicting promises in the meantime.

That is a governance failure, not only a documentation failure.

Build a documentation packet¶

For each public story, keep a short packet with:

target user task
first example or quickstart path
reference page that defines the stable contract
failure or migration note that belongs beside it
executable or review route that keeps the story aligned with code

This packet gives maintainers a concrete way to audit whether the docs are still teaching the right public surface.

Common failure modes¶

showing deep internal imports in public examples
mixing tutorial narrative and stable contract language in one unclear page
leaving the highest-value examples unexecuted so they drift silently
documenting only success paths and ignoring real failure behavior
treating docs changes as lower priority than public API changes

Documentation review card¶

Use this card when reviewing public docs:

Question	What a strong answer sounds like
what supported task does this example teach first?	"run monitoring through the public facade"
does it avoid deep internal imports?	"yes, only supported public paths are shown"
what failure or migration behavior is documented nearby?	"configuration rejection and deprecation guidance"
what keeps the example honest?	"an executable smoke route or snippet check"
what role does this page play?	"tutorial, how-to, reference, or explanation"

Capstone connection¶

Use this page to ask:

which current example still teaches a private import or internal shortcut
which supported workflow should get an executable example first
where the current docs fail to explain a real configuration, failure, or migration path
which page is mixing tutorial and contract language badly enough to confuse learners

That is how documentation becomes part of API governance instead of trailing summary text.

Exit check¶

Leave this lesson only when you can do all of these:

explain why examples publish API promises whether maintainers intend that or not
identify one capstone example that should be executable
identify one place where public docs need a failure-path or migration explanation, not just a happy-path snippet