rag-code-mcp

Tool Output & Indexing Schema (v2)

This document describes the canonical v2 data model used by the code MCP server. The goal is that ANY other developer can quickly understand:

• what is indexed (semantically, into the vector DB),
• what is returned to the AI (structured JSON),
• which tool produces which type of result.

---

1. Indexing / semantic search – CodeChunk

Indexing into the vector DB is done exclusively with the CodeChunk structure (see internal/codetypes/types.go).

// CodeChunk is the canonical v2 format for indexing/search. It represents a
// semantically meaningful piece of code (usually a function, method, type or
// interface declaration) that is stored in vector search.
type CodeChunk struct {
    // Symbol metadata
    Type     string // function | method | type | interface | file
    Name     string // Symbol name (or file base name for Type=file)
    Package  string // Package/module name
    Language string // go | php | python | typescript etc

    // Source location
    FilePath  string
    URI       string
    StartLine int
    EndLine   int

    // Selection range (for precise navigation to symbol name)
    SelectionStartLine int
    SelectionEndLine   int

    // Content
    Signature string
    Docstring string
    Code      string

    // Extra metadata
    Metadata map[string]any
}

Principles:

• CodeChunk is the only format written to the vector DB for code.
• Signature + Docstring + (sometimes) Code is the text that is embedded.
• Metadata can contain language-specific information, for example:
  • Go: type_info (serialized as JSON from golang.TypeInfo),
  • PHP/Laravel: model info (eloquent_model), populated by the Laravel analyzer for Eloquent models (table, fillable, relationships, scopes, attributes, etc.).
• Tools never read raw Metadata directly. They only access it through a layer that builds the descriptors defined below.

---

2. Output for the AI – descriptor schema

All tools that support output_format: "json" must serialize one of the structures defined in internal/codetypes/symbol_schema.go.

2.1. SymbolLocation

type SymbolLocation struct {
    FilePath  string `json:"file_path,omitempty"`
    URI       string `json:"uri,omitempty"`
    StartLine int    `json:"start_line,omitempty"`
    EndLine   int    `json:"end_line,omitempty"`
}

Used everywhere as location for precise navigation.

2.2. ClassDescriptor – type/class/model

type ClassDescriptor struct {
    Language string `json:"language"`
    Kind     string `json:"kind"` // class | interface | trait | struct | type | model
    Name     string `json:"name"`

    Namespace string `json:"namespace,omitempty"`
    Package   string `json:"package,omitempty"`
    FullName  string `json:"full_name,omitempty"`

    Signature   string         `json:"signature,omitempty"`
    Description string         `json:"description,omitempty"`
    Location    SymbolLocation `json:"location,omitempty"`

    Fields    []FieldDescriptor    `json:"fields,omitempty"`
    Methods   []FunctionDescriptor `json:"methods,omitempty"`
    Relations []RelationDescriptor `json:"relations,omitempty"`

    // Data-model specific (ORM / Eloquent)
    Table      string            `json:"table,omitempty"`
    Fillable   []string          `json:"fillable,omitempty"`
    Hidden     []string          `json:"hidden,omitempty"`
    Visible    []string          `json:"visible,omitempty"`
    Appends    []string          `json:"appends,omitempty"`
    Casts      map[string]string `json:"casts,omitempty"`
    Scopes     []string          `json:"scopes,omitempty"`
    Attributes []string          `json:"attributes,omitempty"`

    Tags     []string       `json:"tags,omitempty"`
    Metadata map[string]any `json:"metadata,omitempty"`
}

Used by:

• find_type_definition with output_format: "json".
  • PHP: classes and Laravel models (User, Lawyer, etc.).
  • Go: types (struct/interface), enriched with Fields and Methods from TypeInfo when available.

2.3. FunctionDescriptor – function/method

type FunctionDescriptor struct {
    Language    string         `json:"language"`
    Kind        string         `json:"kind"` // function | method | scope | accessor | mutator | constructor
    Name        string         `json:"name"`
    Namespace   string         `json:"namespace,omitempty"`
    Receiver    string         `json:"receiver,omitempty"`
    Signature   string         `json:"signature,omitempty"`
    Description string         `json:"description,omitempty"`
    Location    SymbolLocation `json:"location,omitempty"`

    Parameters []ParamDescriptor  `json:"parameters,omitempty"`
    Returns    []ReturnDescriptor `json:"returns,omitempty"`

    Visibility string `json:"visibility,omitempty"`
    IsStatic   bool   `json:"is_static,omitempty"`
    IsAbstract bool   `json:"is_abstract,omitempty"`
    IsFinal    bool   `json:"is_final,omitempty"`

    Code     string         `json:"code,omitempty"`
    Tags     []string       `json:"tags,omitempty"`
    Metadata map[string]any `json:"metadata,omitempty"`
}

Used by:

• get_function_details with output_format: "json".
  • PHP: functions and methods, including:
    • visibility, is_static, is_abstract, is_final,
    • parameters (with types from PHPDoc / type-hints),
    • returns (including Eloquent types, e.g. BelongsToMany<App\\Role>),
    • Laravel-specific classification (kind: "scope", "accessor", "mutator" for Eloquent special methods).
  • Go: functions/methods in v2 minimal form (signature, description, code, location), extensible later with parameters/returns parsed from the AST.

2.4. SymbolDescriptor – summary for listings/search

type SymbolDescriptor struct {
    Language  string `json:"language"`
    Kind      string `json:"kind"` // class | interface | trait | function | method | constant | enum | file
    Name      string `json:"name"`
    Namespace string `json:"namespace,omitempty"`
    Package   string `json:"package,omitempty"`

    Signature   string         `json:"signature,omitempty"`
    Description string         `json:"description,omitempty"`
    Location    SymbolLocation `json:"location,omitempty"`

    Tags     []string       `json:"tags,omitempty"`
    Metadata map[string]any `json:"metadata,omitempty"`
}

Used by:

• list_package_exports with output_format: "json" (Go + PHP).
• Search-oriented tools (planned) to return compact hits.

---

3. Mapping: tool → input → output

3.1. find_type_definition

• Standard input:
  • type_name (required),
  • package / namespace (optional but recommended),
  • output_format: "markdown" (default) or "json".
• Output:
  • markdown – human-friendly view, optimized for reading in a terminal.
  • json – a ClassDescriptor instance.

3.2. get_function_details

• Standard input:
  • function_name (required),
  • package / namespace,
  • class_name for PHP methods (implicitly derived from the chunk when possible),
  • output_format.
• Output:
  • markdown – human-friendly view.
  • json – a FunctionDescriptor instance.

3.3. list_package_exports

• Standard input:
  • package / namespace (required),
  • symbol_type (filter; optional),
  • output_format.
• Output:
  • markdown – structured list grouped by kind (function/type/class/etc.).
  • json – []SymbolDescriptor.

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4. Semantic vs structural – how they work together

• Semantic search (recall):
  • operates on CodeChunk + embeddings,
  • tools like hybrid_search / search_code should return:
    • []SymbolDescriptor + small snippets of code.
• Structural / analytic (reasoning):
  • operates on the already-selected chunk,
  • for a specific symbol, the recommended tools are:
    • find_type_definition(json) → ClassDescriptor,
    • get_function_details(json) → FunctionDescriptor,
    • list_package_exports(json) → []SymbolDescriptor.

This way, the AI uses very few tokens on raw code text and instead has a clear, standardized map of symbols via the schema above.

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