How does Atlas ensure Phoenix documentation is up-to-date?

Atlas generates documentation by directly reading your Phoenix application's source code using tools like `lsp` and `read`, ensuring the README reflects the current implementation of LiveViews, Ecto schemas, and contexts, not outdated specifications.

Can Atlas document specific Phoenix components like LiveViews or Ecto schemas?

Yes, Atlas is designed to understand Phoenix-specific constructs. It can enumerate and document the public API of LiveView modules, Ecto schemas with their changesets, and context functions, providing accurate descriptions and usage examples.

What Phoenix commands does Atlas use to verify documentation?

Atlas uses the `bash` tool to execute and verify code samples within the generated README. While it doesn't directly run `mix test (ExUnit)` for documentation verification, it ensures samples are runnable, and the overall workflow encourages running `mix test (ExUnit)` and `mix format` post-generation.

How does Atlas handle existing README files in a Phoenix project?

Atlas uses the `grep` tool to search for existing `README.md` files. This allows it to analyze their structure and tone, ensuring that any new or updated documentation it generates for your Phoenix module maintains consistency with your project's established style.

Is it safe to let Atlas modify my Phoenix codebase for documentation?

Yes, Atlas is built with safety in mind. All tool calls are permission-gated, it drafts a read-only plan for your approval, and it presents a unified diff for every file edit, including `README.md` changes, before writing to your Phoenix project.

Does Atlas support local embedding models for Phoenix code?

Yes, Atlas can build its code index using local Ollama embeddings. This keeps your Phoenix application's code off third-party servers, addressing privacy and security concerns for sensitive projects.

Can Atlas help move Phoenix business logic into contexts?

While the primary job here is documentation, Atlas's capabilities extend to refactoring. It can be asked to move business logic out of a controller into a context function that returns an `ok` or `error` tuple, aligning with Phoenix best practices.

Document a module with a README in Phoenix with Atlas in 2026

Atlas empowers Phoenix developers in 2026 to generate precise README documentation directly from their codebase, ensuring that descriptions reflect the current state of modules, LiveViews, and Ecto schemas. By leveraging tools like `lsp` for API enumeration, `read` for implementation details, and `bash` for verifying code samples, Atlas produces traceable documentation that aligns with your `mix format` standards and passes `mix test (ExUnit)` checks.

How Atlas documents Phoenix modules accurately in 2026

Atlas ensures Phoenix module documentation is accurate in 2026 by directly reading your source code, not relying on memory or outdated specifications. It uses the `lsp` tool's `documentSymbol` operation to enumerate every public API export, guaranteeing 100% coverage of your LiveView, Ecto, and context modules.

Atlas begins the documentation process for a Phoenix module by employing the `lsp` tool's `documentSymbol` operation. This ensures that every public function, macro, or struct exported by your Phoenix module, whether it's a LiveView component, an Ecto schema, or a context function, is identified and included in the documentation. This method prevents any export from being missed or invented, providing a complete and accurate surface area. Following this enumeration, Atlas uses the `read` tool to delve into the implementation of each identified export. For Phoenix-specific constructs like LiveView `handle_info/2` callbacks or Ecto `changeset/2` functions, Atlas reads the actual code to understand its behavior. To further enhance accuracy, Atlas utilizes `codebase_search` to find how these exports are used in practice across your Phoenix application. This might involve examining calls to context functions from controllers, or how LiveView sockets interact with specific components, providing real-world usage examples for the README. This rigorous approach guarantees that the generated documentation reflects precisely what the code does today, not what it was intended to do a year ago.

What Phoenix files and commands does Atlas use for README generation?

Atlas interacts directly with your Phoenix project's file structure and uses standard Elixir commands to ensure documentation fidelity. It reads `mix.exs` for project context, scans `lib/<app>_web` for LiveView and controller modules, and examines `lib/<app>/contexts` for business logic, all within your 2026 codebase.

When generating a README for a Phoenix module, Atlas first uses the `grep` tool to search for any existing `README.md` files within your repository. This step is crucial for matching the established heading structure, tone, and formatting conventions of your project, ensuring the new documentation integrates direct. Atlas then employs the `write` tool to emit the new or updated `README.md` file, incorporating the gathered information. This output includes real function signatures, module attributes, and concrete file paths relevant to your Phoenix application, such as `lib/my_app_web/live/my_live_view.ex` or `lib/my_app/accounts/user.ex`. A critical final step involves the `bash` tool, which Atlas uses to verify every code sample included in the generated documentation. For instance, if the README contains an example of calling a context function or interacting with a LiveView component, Atlas will execute that sample. This verification ensures that all code snippets are runnable and accurate, preventing the inclusion of outdated or incorrect examples that could lead to developer frustration. This process aligns with the expectation that all code in a Phoenix project should pass `mix test (ExUnit)` and adhere to `mix format` standards.

How Atlas ensures safe and reviewable Phoenix documentation edits

Atlas prioritizes safety and transparency when modifying your Phoenix codebase, offering multiple layers of review before any changes are committed. Every Atlas tool call is permission-gated, and it drafts a read-only plan before switching to a build agent, ensuring you have 100% control over the process in 2026.

Atlas incorporates robust safety mechanisms to ensure that documenting a Phoenix module is a controlled and transparent process. Before any Atlas tool, such as `write` or `bash`, is executed, it is permission-gated against `allow`, `ask`, and `deny` rules. This means you, the Phoenix developer, explicitly approve or deny actions, preventing unintended modifications. Furthermore, Atlas operates with a read-only plan agent that drafts a comprehensive strategy for documentation generation. This plan is presented for your review and approval before Atlas switches to a build agent to execute the steps. For every file edit, including the creation or modification of a `README.md` file, Atlas computes and surfaces a unified diff. This allows you to inspect the exact changes before they are written to your Phoenix project. Atlas also reads `git` branches, status, and diffs, and can stage and create commits on your behalf, providing a familiar workflow. It even snapshots file changes as `git` patches, enabling easy diffing and rolling back of edits, ensuring that your Phoenix codebase remains stable and auditable throughout the documentation process.

Step by step

01Initialize Atlas in your Phoenix project: Run `atlas` in your application's root directory, ensuring a `mix.exs` and `lib/<app>_web` directory are present.
02Allow Atlas to index your Phoenix codebase: Let Atlas read your router pipelines, LiveView modules, contexts, and Ecto schemas with their changesets to build its code index.
03Enumerate the module's public API: Use the Atlas `lsp` tool's `documentSymbol` operation to identify all exported functions and macros from your target Phoenix module.
04Gather implementation and usage details: Employ the Atlas `read` tool to understand the behavior of each API, and `codebase_search` to find real-world usage examples within your Phoenix application.
05Determine README structure: Use the Atlas `grep` tool to search for existing `README.md` files in your repository to match their heading structure and tone.
06Draft the module README: Instruct Atlas to use the `write` tool to generate the `README.md` content, quoting real Phoenix signatures and file paths.
07Verify code samples: Allow Atlas to use the `bash` tool to execute and confirm the accuracy of every code sample within the generated documentation.
08Review and approve changes: Inspect the unified diff presented by Atlas for the new `README.md` and approve the write operation, ensuring it aligns with your Phoenix project's standards.
09Format and test your Phoenix project: Run `mix format` to ensure code style consistency and `mix test (ExUnit)` to confirm no regressions were introduced.

Frequently asked questions

How does Atlas ensure Phoenix documentation is up-to-date?: Atlas generates documentation by directly reading your Phoenix application's source code using tools like `lsp` and `read`, ensuring the README reflects the current implementation of LiveViews, Ecto schemas, and contexts, not outdated specifications.
Can Atlas document specific Phoenix components like LiveViews or Ecto schemas?: Yes, Atlas is designed to understand Phoenix-specific constructs. It can enumerate and document the public API of LiveView modules, Ecto schemas with their changesets, and context functions, providing accurate descriptions and usage examples.
What Phoenix commands does Atlas use to verify documentation?: Atlas uses the `bash` tool to execute and verify code samples within the generated README. While it doesn't directly run `mix test (ExUnit)` for documentation verification, it ensures samples are runnable, and the overall workflow encourages running `mix test (ExUnit)` and `mix format` post-generation.
How does Atlas handle existing README files in a Phoenix project?: Atlas uses the `grep` tool to search for existing `README.md` files. This allows it to analyze their structure and tone, ensuring that any new or updated documentation it generates for your Phoenix module maintains consistency with your project's established style.
Is it safe to let Atlas modify my Phoenix codebase for documentation?: Yes, Atlas is built with safety in mind. All tool calls are permission-gated, it drafts a read-only plan for your approval, and it presents a unified diff for every file edit, including `README.md` changes, before writing to your Phoenix project.
Does Atlas support local embedding models for Phoenix code?: Yes, Atlas can build its code index using local Ollama embeddings. This keeps your Phoenix application's code off third-party servers, addressing privacy and security concerns for sensitive projects.
Can Atlas help move Phoenix business logic into contexts?: While the primary job here is documentation, Atlas's capabilities extend to refactoring. It can be asked to move business logic out of a controller into a context function that returns an `ok` or `error` tuple, aligning with Phoenix best practices.

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