What the Data for This Category Looks Like
Data for urban public transit policy and regulatory reference primarily comes from official documents including national bus operation standards released by the Ministry of Transport, local detailed management rules for bus services issued by municipal transport bureaus, fare adjustment announcements, and safety operation procedures. Updates are triggered by policy changes, with no fixed schedule. Updates occur when new policies are released, existing policies are revised, or local policies are adjusted. Document structure follows standard chaptered official format, including standard fields such as release number, issuing unit, effective date, and clause content. Clause content is presented as paragraphs or numbered items, covering topics like fare standards, route adjustment rules, and safety operation requirements. Relevant units include yuan per passenger, operating mileage, and rated passenger capacity.
What Constraints These Characteristics Impose on Knowledge Base Retrieval and Recall
The official nature of public transit policy data requires retrieval results to exactly match the original policy text. Fuzzy matching must be avoided, as it can lead to incorrect interpretations and harm the accuracy of policy implementation. Local policy differences require retrieval to support filtering by issuing unit or location. Without such filtering, cross-region policy confusion may occur, leading users to obtain inapplicable local policies. Formal official document structures often include long paragraphs with strong clause relevance. When chunking documents, full clause integrity must be preserved to avoid semantic breaks that reduce response rigor. The lack of a fixed update cycle requires the knowledge base to support rapid re-chunking and uploading. This adapts to sudden policy changes and ensures retrieved content is always up to date.
Configuration Settings
| Configuration Item | Recommended Setting | Rationale |
|---|---|---|
similarity | 0.75–0.85 | The authoritative nature of policy documents requires high matching accuracy, to avoid retrieving irrelevant non-transit policy content |
limit | Top 8 results | Transit policy clauses are numerous, excessive retrieved results will exceed the context window and harm response coherence |
searchMode | Exact match priority | Clause wording in policy documents is precise, exact matching ensures retrieval results align closely with original text |
usingReRank | Enabled | Re-ranking initial retrieved results prioritizes displaying policy clauses most relevant to user queries |
datasetSearchUsingExtensionQuery | Enabled | Optimizes users' colloquial questions by converting them to professional terminology used in policy documents, improving matching accuracy |
collectionIds | Bind dedicated transit policy knowledge base | Restrict retrieval scope to only policy documents in the transit field, avoid mixing in policy content from other industries |
Three Common Mistakes
- Phenomenon: Enabling tool calling causes the knowledge base retrieval to return empty results. Cause: The knowledge base retrieval module is not configured as a callable node for tool calling, or the dedicated transit policy knowledge base is not bound via the
collectionIdsparameter. - Phenomenon: Retrieval results contain a large volume of non-transit policy content. Cause: The
collectionIdsparameter is not configured, so the retrieval scope covers knowledge base datasets from other industries. - Phenomenon: Unable to filter transit policies for a target city via location tags. Cause: No location tags were added when uploading policy documents to the knowledge base, and no tag filtering rules were configured for the retrieval module.
How to Confirm Proper Configuration
- Access the FastGPT v4.17.0 dataset management interface, confirm that the
collectionIdsparameter points to the dedicated transit policy knowledge base. - Submit a test query: Enter a specific transit policy-related question, verify that retrieval results include corresponding clauses and that the number of results matches the setting of the
limitparameter. - Enable tool calling mode, test calling the knowledge base retrieval tool, confirm that matching policy content is returned normally without empty result errors.
- View retrieval logs, verify that the similarity scores of matching results fall within the range set by the
similarityparameter.
The values provided are common starting points and should be measured against the reader's own samples.
Question material comes from public community discussions. Configuration values are common starting points and should be measured against your own samples. Verified on 2026-09-28.