[Examples] Add agentic search example demonstrating multi-hop RAG pattern

[wachterjohannes]

Q	A
Bug fix?	no
New feature?	no
Docs?	no
Issues	-
License	MIT

Summary

Adds an example demonstrating the agentic search pattern inspired by Chroma's Context 1 model. Instead of single-hop RAG (one query → one result set), an LLM agent iteratively explores a document corpus using four specialized tools:

• corpus_search — Semantic vector search for broad topic discovery (deduplicated across calls)
• corpus_grep — Line-by-line keyword matching on full document content
• corpus_read_document — Full document retrieval by ID, adds to working set
• corpus_prune — Permanently exclude irrelevant documents from future results

Key design decisions

• Search/grep are discovery-only; only read_document adds to the working set
• Search results are deduplicated across calls (already-seen documents are filtered)
• Pruned documents are permanently excluded from all future search and grep results
• Grep searches original document content line-by-line (not embeddings), making it genuinely different from semantic search
• One document per movie (detailed markdown preferred over short descriptions)

Files

• fixtures/AgenticSearch/DocumentCorpus.php — Shared state: store, deduplication, pruning, working set
• fixtures/AgenticSearch/AgenticSearchTools.php — 4 tools in one class using multi-#[AsTool] pattern
• examples/rag/agentic-search.php — Example wiring with event-based tool call logging

Usage

cd examples && php rag/agentic-search.php

[chr-hertel]

Super interesting - feels like we need more movies :D

[wachterjohannes]

@chr-hertel added movies and improved the script :)

[wachterjohannes]

@chr-hertel removed unused method

[chr-hertel]

Thank you @wachterjohannes.