Card: add "Using it from an agent"

A five-step pattern for agents (find, read the whole section, check the
version in force, follow references both ways, cite precisely) with
runnable helpers: read_section, versions, in_force and references.
Data files are unchanged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

README.md

@@ -217,6 +217,75 @@ separate, it resolves to the first.
 | `subdivision` | The cited subsection, such as `(a)(3)`, when there is one |
 | `block_label` | The subsection of the source chunk where the citation appears |
 
+## Using it from an agent
+
+The dataset is laid out for an agent that answers questions about Tennessee law
+and has to cite what it used. The pattern:
+
+1. **Find candidates.** Index `text` with your embedding model or BM25; the
+   chunks are already sized for retrieval. Keep each chunk's `id` with it.
+2. **Read the whole section.** A chunk is part of a section. Before relying on
+   one, read every chunk with the same `section_id`, in `chunk_index` order.
+3. **Check which version is the law.** A cite can have several documents. List
+   them and use the qualifier to pick the one in force on the date that
+   matters. A contingency has no date, so say that instead of choosing.
+4. **Follow the references.** Outbound edges lead to the sections this one relies
+   on, such as its definitions; inbound edges show what depends on it. An
+   unresolved edge points outside this dataset: report it as not covered, never
+   as not existing.
+5. **Cite precisely.** Give `meta.document_title`, the `section_id`, the currency
+   line and `source_url`.
+
+```python
+import datetime as dt
+from datasets import load_dataset
+
+chunks = load_dataset("ChrisScr770/tennessee-code", "chunks", split="train").to_pandas()
+edges = load_dataset("ChrisScr770/tennessee-code", "crossrefs", split="train").to_pandas()
+firsts = chunks[chunks.chunk_index == 1]  # one row per document
+
+def read_section(section_id):
+    """Every chunk of one document, in order."""
+    rows = chunks[chunks.section_id == section_id].sort_values("chunk_index")
+    return "\n\n".join(rows.text)
+
+def versions(cite):
+    """Each document published under a cite, with what tells them apart."""
+    rows = firsts[firsts.cite == cite]
+    return [(r.section_id, r.meta["version_qualifier"], r.meta["effective_note"])
+            for r in rows.itertuples()]
+
+def in_force(section_id, on=None):
+    """True or False where the qualifier decides; None where a person has to."""
+    row = firsts[firsts.section_id == section_id].iloc[0]
+    qualifier = row.meta["version_qualifier"]
+    day = (on or dt.date.today()).isoformat()
+    if qualifier.startswith("until-"):
+        return day < qualifier.removeprefix("until-")
+    if qualifier.startswith("on-"):
+        return day >= qualifier.removeprefix("on-")
+    if qualifier in ("reserved", "repealed"):
+        return False
+    if qualifier:  # a contingency: the text takes effect on an event, not a date
+        return None
+    undated = [v for v in versions(row.cite) if not v[1]]
+    return True if len(undated) == 1 else None  # .vN twins: read both
+
+def references(section_id):
+    """Outbound: what this section cites. Inbound: what cites it."""
+    ids = chunks.id[chunks.section_id == section_id]
+    cite = firsts.cite[firsts.section_id == section_id].iloc[0]
+    outbound = edges[edges.source_chunk_id.isin(ids)]
+    inbound = edges[(edges.target_cite == cite) & ~edges.source_chunk_id.isin(ids)]
+    return outbound, inbound
+
+for section_id, qualifier, note in versions("37-3-803"):
+    print(section_id, in_force(section_id))
+```
+
+The dataset's author serves this same pattern to agents as MCP tools (search,
+read a section, follow its references); the server itself is not published.
+
 ## Source and method
 
 The text was converted from the free public-access Tennessee Code that

export_manifest.json

@@ -2,8 +2,8 @@
  "dataset": "Tennessee Code Unannotated (Titles 29, 34, 36, 37, 39, 40 and 41)",
  "repo_id": "ChrisScr770/tennessee-code",
  "license": "cc0-1.0",
- "exported_at": "2026-10-08T05:57:31+00:00",
- "source_commit": "2a688d506d22e294baab8b9b026d14cba88a1ae2",
+ "exported_at": "2026-10-08T06:13:08+00:00",
+ "source_commit": "f6076a9578e38add9a002073c0a06c38027859a7",
  "source_dirty": false,
  "currency": "Current through the 2026 Regular Session and the 2026 2nd Extraordinary Session.",
  "code_datestamp": "2026-09-30T15:52:38.000244-00:00",