## What Adds CI enforcement that fails when docs Markdown contains invalid inline HTML the docs site silently drops or mangles, and fixes the remaining generated-doc placeholders at their source. This is the tooling half of the docs-HTML audit. The hand-written fixes it guards landed in #27298 (kept small and separate so it reviewed fast); this PR carries everything that touches code, CI, or generated output. ## Changes **Linter (`scripts/docshtmlcheck`), wired into `make lint` via `lint/docs-html`.** Markdown-aware: parses each file with goldmark and inspects only raw-HTML nodes, so angle brackets in fenced code blocks, inline code, HTML comments, and `<https://…>` / `<user@host>` autolinks are ignored. Flags swallowed placeholders (`<region>`), void-element end tags (`</br>`), unregistered or incorrectly capitalized component tags (`<Image>`), and unclosed container tags (a `<div class="tabs">` that leaks its wrapper). The one intentional renderer component, `<children>`, is allowed but still balance-checked. **Generator-source placeholder fixes (regenerated via `make gen`).** - `codersdk/chats.go`: backtick `<server>__` in the `ChatContextTool.Name` doc comment (it becomes the Swagger description, so it was swallowed in `reference/api/{chats,schemas}.md`). - `codersdk/deployment.go`: backtick `<region>` in the AWS Bedrock region flag help (swallowed in `reference/cli/server.md`); also updates `coder server --help` output and the golden files. **Temporary allowlist.** `docs/reference/cli/agent-firewall.md`'s `<host>` / `<glob>` come from the external `github.com/coder/boundary` CLI help (still `v0.10.0` on `main`), so they are suppressed on that one file. The suppression is self-clearing: if an allowlisted tag stops appearing on a scanned file, the linter reports `stale-allowlist-entry` and fails until the dead entry is removed, so a dead entry cannot silently mask a later regression of that tag on that page. (An entry whose file is deleted outright is never rescanned, but a missing file yields no findings, so nothing hides behind it either.) ## Review feedback addressed This tool + generator work was reviewed by Coder Agents Review while it was bundled into #27298. Addressed here: - **P1:** tokenize each raw-HTML node as a whole instead of per source line, so a tag whose attributes wrap across lines is no longer torn in half. This fixes both the missed multi-line unclosed `<div>` (a leaked wrapper that passed with exit 0) and the spurious `stray-end-tag` on valid multi-line tags. Each token maps back to its own source line. - Normalize allowlist lookup/report paths to a canonical repo-relative form, so the escape hatch no longer silently misses under absolute / `./` paths. - Route generated-page findings to the generator source. - Add `<search>` to the allowed set; reword the unknown-element message to note that a real element can be added to `allowedElements`. - Self-clearing allowlist guard (above); rename `optionalEndTag(s)` and `kindUnclosed(Tag)`; adopt `slices`/`maps` idioms; move the lint banner to the Makefile recipe; stop aliasing the input slice in `filterAllowed`. - New tests: multi-line tokenization (both classes), interleaved nesting, a pinned line number, `collectMarkdown`, and the stale-allowlist guard. ### Round 2 (Coder Agents Review on this PR) A second `/coder-agents-review` pass on this PR raised 16 findings; addressed in `fix(docshtmlcheck): catch self-closing containers and capitalized tags`: - **P2:** self-closing container tags (`<div class="tabs"/>`) were ignored by the HTML5 parser and leaked their wrapper like the open spelling; the balance check now tracks self-closing tokens too (CRF-1). - **P2:** a capitalized component tag whose lowercase name is a real element (`<Table>`, `<Section>`) slipped through on the `allowedElements` lookup. The tokenizer lowercases tag names, so the check now reads the raw token and reports any capitalized name as a component reference (CRF-2). - Narrowed the `:` / `@` autolink skip to a real URI scheme or a dotted `local@domain`, so `<region:id>` and `<user@host>` stay checked (CRF-3). - Stale-allowlist findings now report against the linter source with no line, and count separately from invalid-HTML issues in the footer (CRF-7, CRF-11). - Comment / README / Makefile wording synced to the honest capitalized-tag behavior; added the deleted-file allowlist caveat and a note that `allowedElements` is hand-maintained against the renderer (CRF-14, CRF-17, CRF-9). - Internal cleanups (`pop` -> `matchEndTag`, extracted `unclosedFinding`) and new tests: self-closing, capitalized open/close, colon/at placeholders, a non-first-token line assertion, `isGeneratedDoc`, and the stale message (CRF-12, CRF-13, CRF-1/2/3/4/5/16). Two findings resolved without a code change: - **CRF-8** (also wire `lint/docs-html` into `lint-light`): declined. `lint-light` is the Go-free fast path; `lint/docs-html` needs the Go toolchain, so it stays in the full `make lint`, which CI runs. Adding it would pull Go into the light path for no coverage gain. - **CRF-9** (`allowedElements` <-> renderer coupling): documented with a maintenance note in the `allowedElements` comment and tracked in DOCS-597 for a cross-repo sync/check decision. Deferred (note, no current trigger): raw-text element interiors (`<script>` / `<style>`) are not scanned for nested tags. No docs page relies on this today; noted for follow-up. ## Merge order #27298 (the hand-written fixes this PR guards) has merged, and this branch is rebased on `main`, so `make lint/docs-html` now reports 0 findings and the `lint` check passes. The two PRs are independent (disjoint files, no stacking). ## Verification - `go test ./scripts/docshtmlcheck/`, `go vet`, `gofmt -l`, `golangci-lint run`: clean. - `make lint/docs-html` (branch rebased on `main`): 0 findings. ## Linear - DOCS-584: https://linear.app/codercom/issue/DOCS-584/add-ci-check-that-fails-on-invalid-inline-html-in-docs - DOCS-551: https://linear.app/codercom/issue/DOCS-551/backtick-placeholder-syntax-in-generated-reference-docs-cli-help - DOCS-597 (follow-up, from CRF-9): https://linear.app/codercom/issue/DOCS-597/track-docshtmlcheck-allowedelements-drift-vs-docs-renderer-component > This PR was created with AI assistance (Coder Agents).
About
Coder is a self-hosted platform for running AI coding agents and cloud development environments on infrastructure you control. It works with any cloud, IDE, OS, Git provider, and IDP.
Coder Workspaces
Coder Workspaces are cloud development environments defined with Terraform, connected through a secure Wireguard tunnel, and automatically shut down when not in use. Agents and developers share the same workspace infrastructure.
- Defined in Terraform: Templates describe the infrastructure for each workspace, from EC2 VMs and Kubernetes Pods to Docker containers.
- Any architecture and OS: Support ARM and x86-64 across Windows, Linux, and macOS from a single deployment.
- Managed by admins: Platform teams create and maintain templates that enforce approved images, resource limits, and security policies.
- Accessed from any IDE: Connect through VS Code, JetBrains, Cursor, a web terminal, remote desktop, or SSH.
- Automatic shutdown: Idle workspaces stop automatically to reduce cloud spend, and restart in seconds when needed.
Coder Agents
Coder Agents is a native AI coding agent built into Coder. The agent loop runs in the Coder control plane on your infrastructure, not in the workspace and not in a vendor's cloud. Developers interact with agents through the web UI or the REST API for programmatic and CI-driven workflows.
- Self-hosted agent loop: The control plane handles planning, model calls, and tool dispatch. Workspaces have zero AI awareness.
- No API keys in workspaces: LLM credentials stay in the control plane.
- Any model: Anthropic, OpenAI, Google, Bedrock, or self-hosted endpoints. Switching is a configuration change.
- Governance and cost controls: Centralized model approval, per-user spend limits, and audit logging.
- Open source and inspectable: The full platform is available to audit and extend.
IDE support
You can use:
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Any Web IDE, such as
- code-server
- JetBrains Projector
- Jupyter
- And others
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Your existing remote development environment:
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A file sync such as Mutagen
Why remote development
Provisioning consistent development environments for a large engineering team is difficult. Each developer has preferences for operating systems, editors, and toolchains, and ensuring a reliable build environment across all of them is a maintenance burden. A missed step during onboarding or an unsupported local configuration can cost hours of debugging.
Remote development solves this by moving the environment off the developer's machine and into managed infrastructure. The developer's laptop becomes a portal into the actual compute where work happens. If a device is lost or replaced, access is simply revoked; no source code or credentials are stored locally.
This approach provides:
- Speed: Server-grade hardware accelerates builds, tests, and large workloads without requiring expensive local machines.
- Consistency: Infrastructure tools such as Terraform, nix, Docker, and Dev Containers produce identical environments for every developer.
- Security: Source code stays on private servers. Users and groups are managed through SSO and RBAC.
- Compatibility: Workspaces share infrastructure configurations with staging and production, reducing configuration drift.
- Accessibility: Browser-based IDEs and remote IDE extensions let developers work from any device, including lightweight laptops, Chromebooks, and tablets.
Read more on the Coder blog, the Slack engineering blog, or from Alex Ellis at OpenFaaS.
Why Coder
The key difference between Coder and other platforms is that the entire system, agent loop, control plane, model routing, and workspace provisioning, runs on infrastructure you control.
For agents, this means platform teams can:
- Run the entire agent loop on their infrastructure, with no SaaS dependency for orchestration.
- Define MCP servers, skills, and system prompts centrally so every agent session starts with the same tools, policies, and context.
- Keep LLM credentials out of workspaces entirely.
- Tie every agent action to an authenticated user identity.
- Support air-gapped and restricted-network deployments with self-hosted models.
For workspaces, this means admins can:
- Support any architecture (ARM, x86-64) and operating system (Windows, Linux, macOS).
- Modify pod/container specs, such as adding disks, managing network policies, or setting/updating environment variables.
- Use VM or dedicated workspaces, developing with Kernel features (no container knowledge required).
- Enable persistent workspaces, which are like local machines, but faster and hosted by a cloud service.
Pricing
Coder is free and open source under the GNU Affero General Public License v3.0. All developer productivity features are included in the open source version. A Premium license is available for enhanced support and custom deployments.
How Coder works
Coder workspaces are represented with Terraform, but you do not need to know Terraform to get started. The Coder Registry provides production-ready templates for AWS EC2, Azure, Google Cloud, Kubernetes, and other providers.
Providers and compute environments
Workspaces can include more than just compute. Terraform can add storage buckets, secrets, sidecars, and other resources.
See the templates documentation for details.
What Coder is not
-
Coder is not an infrastructure as code (IaC) platform.
- Terraform is the first IaC provisioner in Coder, allowing Coder admins to define Terraform resources as Coder workspaces.
-
Coder is not a DevOps/CI platform.
- Coder workspaces can be configured to follow best practices for cloud-service-based workloads, but Coder is not responsible for how you define or deploy the software you write.
-
Coder is not an online IDE.
- Coder supports common editors, such as VS Code, vim, and JetBrains, all over HTTPS or SSH.
-
Coder is not a collaboration platform.
- You can use Git with your favorite Git platform and dedicated IDE extensions for pull requests, code reviews, and pair programming.
-
Coder is not a SaaS/fully-managed offering.
- Coder is a self-hosted solution. You must host Coder in a private data center or on a cloud service, such as AWS, Azure, or GCP.

