Everyday Scenarios

In this chapter you see how the tools combine into the tasks developers repeat every day. Each scenario shows a prompt you can paste, the tools the assistant uses, and why the result is more reliable than text search.

Prerequisites

• A working connection and your first query.

Understand unfamiliar code

Give me an outline of src/billing.rs and explain what calculate_total does.

The assistant calls get_document_symbols for the structure of the file, then get_hover on calculate_total for its signature and documentation. Both come from the language server, so signatures are exact.

Trace where something is used

Where is calculate_total called, and which functions call it?

1. get_references lists every usage across the workspace.
2. prepare_call_hierarchy and get_incoming_calls show the calling functions, grouped by caller.

Add “and tell me which function each usage is inside” and the assistant passes context: "enclosing_symbol", so every location comes with the function or type that contains it.

Plan a safe rename

Rename process_data to handle_data everywhere and show me the plan.

1. prepare_rename checks that the symbol can be renamed.
2. rename_symbol returns the edits for every file.

mcpls returns the edits; it does not write them. The assistant applies them with its own file tools, after you approve. If the result contains a dropped field, some edits were withheld (for example files outside the workspace) and the rename is incomplete, so the assistant should say so before applying anything.

Fix compiler errors

Fix the errors in src/lib.rs.

get_diagnostics provides the exact messages and ranges. get_code_actions can add the quick fixes the language server offers, such as adding a missing import.

Navigate to the right implementation

Which types implement the Storage trait?

go_to_implementation jumps from a trait method to its implementations; prepare_type_hierarchy with get_subtypes lists implementors for languages whose server supports type hierarchy. go_to_type_definition answers “what type is this value?” by jumping to the type itself.

Look up a symbol you cannot place

Where is something called SessionManager defined?

workspace_symbol_search searches names across the whole workspace, so the assistant does not need a file first.

What’s Next

Before you tune anything, read Minimal Configuration to see how little setup a first project needs.