What this category of data looks like
Data for urban investment platform declaration materials and file review mainly comes from project initiation declaration documents, land transfer approval dossiers, urban investment bond issuance declaration materials, public utility operation filing dossiers, and similar sources. The data update rhythm fluctuates with project cycles: updates are dense during concentrated declaration periods, and sporadic supplementary archiving occurs daily. Documents include structured fields and unstructured text. Structured fields include project number, investment amount, land area, and similar items, with units such as ten thousand yuan, mu, square meters, and similar units. Unstructured content mostly consists of multi-page approval explanations and supporting materials, with a wide span in the length of individual documents.
What constraints these characteristics impose on the vector model and indexing link
The mixed structured and unstructured nature of urban investment platform declaration and file data requires indexes to support joint retrieval of multiple data types. The wide variation in individual document length requires flexible configuration for long text chunking to avoid splitting key approval information. The concentrated update rhythm and bulk archived historical data require indexes to support bulk initialization and incremental update adaptation. The high proportion of standardized content requires adjusting vector model matching rules to filter invalid template matches and ensure retrieval accuracy.
How to set the configurations
| Configuration Item | Recommended Setting | Rationale |
|---|---|---|
| Chunk Length | 800–1200 characters | Adapt to the content integrity of long paragraphs in urban investment declaration materials, avoid splitting key approval information |
| Overlap Length | 100–150 characters | Reduce context breaks after chunking, ensure retrieval continuity of dossier-related content |
| Similarity Threshold | 0.72–0.85 | Filter invalid high matching results from urban investment standardized declaration templates, accurately match core review needs |
| Single Search Limit | Top 10 results | Cover retrieval needs for multiple related dossiers, avoid retrieving excessive redundant content |
maxToken | 8000 token | Adapt to context splicing for long declaration materials, comply with the general large model input limits of FastGPT v4.17.0 |
defaultToken | Calibrate based on actual testing | Token distribution varies greatly across different batches of declaration materials, adjust the baseline value according to actual imported data |
Three common mistakes
- Phenomenon: When creating a knowledge base, if the ada 002 vector model is not selected, the interface displays the error prompt
undefined model must match "^(text". Reason: The platform's default vector model verification rules do not adapt to third-party models outside the ada series, and the model configuration path needs to be manually supplemented. - Phenomenon: Semantic retrieval returns high scores, but the results do not match actual declaration and review requirements. Reason: The similarity threshold has not been adjusted for urban investment standardized declaration materials, and templated content leads to invalid high matching.
- Phenomenon: Search recall results only include the main declaration materials, and do not include related auxiliary dossiers. Reason: The vectorization index switch for auxiliary data has not been enabled, so auxiliary files are not included in the retrieval scope.
How to confirm the configuration is correct
- Upload a typical urban investment project declaration material, check whether the text fragments in the chunk preview interface cover complete approval node explanations.
- Trigger a dossier retrieval, view the similarity score distribution of the returned results, and confirm that the filtered results meet the core review needs.
- Import an auxiliary dossier file, verify whether the retrieval results include relevant content fragments of the auxiliary file.
- View the vector model configuration page, confirm that the version of the selected model matches the text format of the imported data.
The values listed above 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.