fix(mcp): harden tool errors, limits and cache

.github/workflows/ci.yml

@@ -37,7 +37,7 @@ jobs:
         run: cargo fmt --all -- --check
 
       - name: Run Clippy Linter (cargo clippy)
-        run: cargo clippy --all-targets -- -D warnings
+        run: cargo clippy --locked --all-targets -- -D warnings
 
       - name: Run Automated Tests (cargo test)
-        run: cargo test --all --verbose
+        run: cargo test --all --locked --verbose

.gitignore

@@ -1,7 +1,6 @@
 # Generated by Cargo
 /target/
 **/*.rs.bk
-Cargo.lock
 
 # Environment & Secrets (Never commit secrets!)
 .env

CHANGELOG.md

@@ -5,6 +5,17 @@ All notable changes to **DocuGraph MCP** will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+### Fixed
+- **MCP tool errors:** unknown documents, sections, pages and attachments return `isError: true` with a message that lists what is available, instead of a successful result or a fake "Document Not Found" object.
+- **Unknown `document_id` in searches:** `document_search`, `document_search_hybrid`, `document_get_context` and `document_get_evidence` return an error listing the indexed ids instead of silently searching every document.
+- **Page ranges and sizes:** `document_read_pages` validates `1 <= page_start <= page_end` and clamps `page_end` to the last page, so `page_end = 4294967295` answers in milliseconds. `limit`, `max_tokens`, `max_chunks`/`max_items`, `max_chars` and `max_bytes` are capped, and `limit * 3` no longer overflows.
+- **Empty or misplaced cache:** `document_list` names the absolute cache directory and `DOCUGRAPH_CACHE_DIR` when it finds no documents, and `docugraph serve` warns on stderr about a relative or empty cache directory.
+
+### Added
+- End-to-end stdio test that runs `docugraph serve`, checks `isError` on failed tool calls and that stdout only carries JSON-RPC.
+
 ## [0.1.0] - 2026-09-13
 
 ### Added

CONTRIBUTING.md

@@ -51,6 +51,9 @@ cargo clippy --all-targets -- -D warnings
 
 # 3. Suite completa de pruebas pasando
 cargo test --all
+
+# 4. (Opcional) Test con un PDF real, ignorado por defecto
+DOCUGRAPH_TEST_PDF=/ruta/a/libro.pdf cargo test --test pdf_ingestion_test -- --ignored
 ```
 
 ---