Remove some duplicated rules

CLAUDE.md

@@ -51,7 +51,9 @@ mise run dev:setup
 # Run the Phoenix server
 mix phx.server
 
-# Run with an interactive Elixir console
+# Run the server with an interactive Elixir console.
+# Note that if you can access the configured MCP server, the application server
+# is already running
 iex -S mix phx.server
 # OR
 mise run dev:console
@@ -190,25 +192,6 @@ Naming Conventions
 - Use PascalCase for module names.
 - Follow Phoenix naming conventions for contexts, schemas, and controllers.
 
-Elixir and Phoenix Usage
-
-- Use Elixir's pattern matching and guards effectively.
-- Leverage Phoenix's built-in functions and macros.
-- Use Ecto effectively for database operations.
-
-Syntax and Formatting
-
-- Follow the Elixir Style Guide (<https://github.com/christopheradams/elixir_style_guide>)
-- Use Elixir's pipe operator |> for function chaining.
-- Prefer single quotes for charlists and double quotes for strings.
-
-Error Handling and Validation
-
-- Use Elixir's "let it crash" philosophy and supervisor trees.
-- Implement proper error logging and user-friendly messages.
-- Use Ecto changesets for data validation.
-- Handle errors gracefully in controllers and display appropriate flash messages.
-
 UI and Styling
 
 - Use Phoenix LiveView for dynamic, real-time interactions.
@@ -248,29 +231,36 @@ Follow the official Phoenix guides for best practices in routing, controllers, c
 
 <!-- usage-rules-start -->
 <!-- usage-rules-header -->
+
 # Usage Rules
 
-**IMPORTANT**: Consult these usage rules early and often when working with the packages listed below. 
-Before attempting to use any of these packages or to discover if you should use them, review their 
+**IMPORTANT**: Consult these usage rules early and often when working with the packages listed below.
+Before attempting to use any of these packages or to discover if you should use them, review their
 usage rules to understand the correct patterns, conventions, and best practices.
+
 <!-- usage-rules-header-end -->
 
 <!-- igniter-start -->
+
 ## igniter usage
+
 _A code generation and project patching framework
 _
 
 [igniter usage rules](deps/igniter/usage-rules.md)
+
 <!-- igniter-end -->
 <!-- usage_rules-start -->
+
 ## usage_rules usage
+
 _A dev tool for Elixir projects to gather LLM usage rules from dependencies
 _
 
 ## Using Usage Rules
 
-Many packages have usage rules, which you should *thoroughly* consult before taking any
-action. These usage rules contain guidelines and rules *directly from the package authors*.
+Many packages have usage rules, which you should _thoroughly_ consult before taking any
+action. These usage rules contain guidelines and rules _directly from the package authors_.
 They are your best source of knowledge for making decisions.
 
 ## Modules & functions in the current app and dependencies
@@ -289,10 +279,9 @@ mix usage_rules.docs Enum.zip
 mix usage_rules.docs Enum.zip/1
 ```
 
-
 ## Searching Documentation
 
-You should also consult the documentation of any tools you are using, early and often. The best 
+You should also consult the documentation of any tools you are using, early and often. The best
 way to accomplish this is to use the `usage_rules.search_docs` mix task. Once you have
 found what you are looking for, use the links in the search results to get more detail. For example:
 
@@ -310,22 +299,26 @@ mix usage_rules.search_docs "making requests" -p req
 mix usage_rules.search_docs "Enum.zip" --query-by title
 ```
 
-
 <!-- usage_rules-end -->
 <!-- usage_rules:elixir-start -->
+
 ## usage_rules:elixir usage
+
 # Elixir Core Usage Rules
 
 ## Pattern Matching
+
 - Use pattern matching over conditional logic when possible
 - Prefer to match on function heads instead of using `if`/`else` or `case` in function bodies
 
 ## Error Handling
+
 - Use `{:ok, result}` and `{:error, reason}` tuples for operations that can fail
 - Avoid raising exceptions for control flow
 - Use `with` for chaining operations that return `{:ok, _}` or `{:error, _}`
 
 ## Common Mistakes to Avoid
+
 - Elixir has no `return` statement, nor early returns. The last expression in a block is always returned.
 - Don't use `Enum` functions on large collections when `Stream` is more appropriate
 - Avoid nested `case` statements - refactor to a single `case`, `with` or separate functions
@@ -338,13 +331,15 @@ mix usage_rules.search_docs "Enum.zip" --query-by title
 - There are many useful standard library functions, prefer to use them where possible
 
 ## Function Design
+
 - Use guard clauses: `when is_binary(name) and byte_size(name) > 0`
 - Prefer multiple function clauses over complex conditional logic
 - Name functions descriptively: `calculate_total_price/2` not `calc/2`
-- Predicate function names should not start with `is` and should end in a question mark. 
+- Predicate function names should not start with `is` and should end in a question mark.
 - Names like `is_thing` should be reserved for guards
 
 ## Data Structures
+
 - Use structs over maps when the shape is known: `defstruct [:name, :age]`
 - Prefer keyword lists for options: `[timeout: 5000, retries: 3]`
 - Use maps for dynamic key-value data
@@ -357,7 +352,8 @@ mix usage_rules.search_docs "Enum.zip" --query-by title
 - Read the docs and options fully before using tasks
 
 ## Testing
-- Run tests in a specific file with `mix test test/my_test.exs` and a specific test 
+
+- Run tests in a specific file with `mix test test/my_test.exs` and a specific test
   with the line number `mix test path/to/test.exs:123`
 - Limit the number of failed tests with `mix test --max-failures n`
 - Use `@tag` to tag specific tests, and `mix test --only tag` to run only those tests
@@ -365,26 +361,32 @@ mix usage_rules.search_docs "Enum.zip" --query-by title
 
 <!-- usage_rules:elixir-end -->
 <!-- usage_rules:otp-start -->
+
 ## usage_rules:otp usage
+
 # OTP Usage Rules
 
 ## GenServer Best Practices
+
 - Keep state simple and serializable
 - Handle all expected messages explicitly
 - Use `handle_continue/2` for post-init work
 - Implement proper cleanup in `terminate/2` when necessary
 
 ## Process Communication
+
 - Use `GenServer.call/3` for synchronous requests expecting replies
 - Use `GenServer.cast/2` for fire-and-forget messages.
 - When in doubt, us `call` over `cast`, to ensure back-pressure
 - Set appropriate timeouts for `call/3` operations
 
 ## Fault Tolerance
+
 - Set up processes such that they can handle crashing and being restarted by supervisors
 - Use `:max_restarts` and `:max_seconds` to prevent restart loops
 
 ## Task and Async
+
 - Use `Task.Supervisor` for better fault tolerance
 - Handle task failures with `Task.yield/2` or `Task.shutdown/2`
 - Set appropriate task timeouts