What data for this category looks like
Data comes from stress, temperature sensing, vibration, and settlement monitoring devices deployed along tunnel routes, as well as status collection systems for operation and maintenance equipment such as ventilation and lighting systems. Updates push single or aggregated alert entries every 10 seconds to 1 minute. Most documents use structured JSON or table formats, with fields including alert ID, associated device number, alert type, trigger threshold, occurrence time, corresponding tunnel section, current status, and units such as degrees Celsius, millimeters per second, and millimeters.
Constraints imposed on knowledge base retrieval and recall
The structured nature of tunnel alert data requires retrieval to precisely match core fields such as device number and alert type, to avoid irrelevant recall results. The real-time collection rhythm requires the knowledge base to support high-frequency incremental synchronization. Without this, recall results cannot cover the latest alert rules and device status. Single data entries have a small volume, but total entries increase as tunnel mileage grows. This requires limiting the number of single-recall results to prevent context overflow. Alert types cover multiple categories of physical anomalies. Invalid alerts must be filtered using business rules, so the retrieval link must associate preset filtering conditions.
Configuration Settings
Reference only; verify against the target FastGPT release and deployment documentation.
| Configuration Item | Recommended Setting | Rationale |
|---|---|---|
similarity | 0.78–0.82 | Tunnel alerts require precise matching of core fields such as device number and alert type. This range filters out irrelevant alerts while retaining valid matching results |
limit | Top 10 entries | Single alert data has a small volume. Too many recalls will exceed the context length limit, while too few will fail to cover associated historical alert rules |
searchMode | Hybrid retrieval | Combines structured fields and vector features to adapt to the multi-field attributes of alert data |
usingReRank | Enabled | Performs a secondary sort of initial recall results by business relevance to filter mis-matched alert entries |
datasetSearchUsingExtensionQuery | Enabled | Generates extended query terms based on alert content to cover matching scenarios for synonyms or professional terms |
collectionIds | Bind a dedicated alert knowledge base collection | Avoid confusion with data from other category knowledge bases and ensure precise retrieval scope |
Three Common Misconfigurations
- Phenomenon: An
undefined model must match "^(texterror is returned when calling the retrieval interface. Cause: An officially compatible embedding model was not selected. The structured characteristics of tunnel alert data require an embedding model that supports vector retrieval. Specifying no model or selecting an incompatible model will trigger a verification error. - Phenomenon: A large number of irrelevant non-tunnel alert entries are mixed in the retrieval results. Cause: A dedicated alert knowledge base collection was not bound. The retrieval scope covers documents from other categories, resulting in recall results that do not fit the business scenario.
- Phenomenon: Local knowledge base reference content is displayed in conversations even when no local knowledge base is associated. Cause: The knowledge base reference display switch for the conversation was not turned off, or the default reference display logic was retained in the retrieval configuration. This forces pending verification content to be displayed even when no matching knowledge base exists.
How to Verify Proper Configuration
- Upload a single tunnel alert test data set, perform a retrieval action, and check whether the recall results include matching alert rule documents.
- Adjust the
similarityparameter range, observe changes in the number of recall results, and confirm that the parameter's control over the retrieval scope meets expectations. - Disable the
usingReRankconfiguration, compare the sorting logic of recall results before and after, and confirm that the re-ranking function works correctly. - Check the binding status of the knowledge base collection, confirm that it only contains documents related to tunnel alerts, with no redundant data from other categories.
The values provided here are common starting points and should be evaluated 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.