What this category of data looks like
Data related to railway operation service inquiries and responses mainly comes from official service guide PDFs released by passenger departments, station announcement documents, customer service center inquiry response archives, and supporting service rule documents such as train schedule adjustments and ticket reissuance. The data updates in real time with new policies. Daily operation documents are archived daily. Regulatory documents are revised quarterly. Most documents have multi-level nested structured content, including fields such as regulation number, effective date, applicable section, and charging standards. Units involve transportation-related standard units like kilometers, hours, and yuan.
Constraints on Document Parsing and Chunking
The multi-level nested structure of railway service inquiry documents causes linear chunking to lose hierarchical connections. Deploy chunking logic that preserves directory structures. Real-time updated policy documents require fast parsing response times to avoid delayed ingestion of newly released service guides. Long customer service response records and regulatory documents will have complete information units containing effective dates and applicable sections truncated if chunking parameters are set incorrectly. This reduces subsequent retrieval accuracy. Additionally, unit fields like kilometers and hours in documents must not be split between the unit and associated numerical values. This ensures information integrity during retrieval.
Configuration Settings
| Configuration Item | Recommended Setting | Rationale |
|---|---|---|
chunkSize | 800–1200 characters | Matches the single-paragraph information length of railway regulations and customer service responses, avoids truncating complete rules or response content |
chunkSplitter | Split by heading hierarchy | Aligns with the multi-level nested structure of documents, preserves hierarchical associations of service processes, prevents chunking from breaking directory logic |
customPdfParse | Enable railway-specific preset template | Adapts to the header, footer, and regulation number formatting of official railway PDFs, reduces redundant page identifier content in parsing |
PARSE_FILE_TIMEOUT_SECONDS | 60–90 seconds | Covers the time requirements for long document parsing, prevents parsing failures for real-time updated policy documents due to timeout |
chunkSettingMode | Manual configuration | Supports adjusting chunking parameters for different document types (regulations/responses/announcements), adapts to the diverse structures of railway documents |
Three Common Mistakes
- Phenomenon: No configuration entry is found when using an external PDF-maker parser. The interface displays an error indicating an unbound parsing key. Cause: The external parser key was not bound in the
customPdfParseconfiguration item of the FastGPT backend, or the custom parsing switch was not enabled. - Phenomenon: Only top-level content is parsed from Feishu multi-level directory documents. Doc documents and images cannot be retrieved. Cause: The multi-level directory recursive parsing switch was not enabled, and image OCR parsing parameters were not configured. Non-text content is not extracted.
- Phenomenon: Split-related error logs appear when using Marker. No parsing results are returned in a Docker deployment environment. Cause: The splitting rule configured for the
chunkSplitterparameter conflicts with Marker's internal splitting logic, or the chunk length setting exceeds Marker's default processing limit.
How to Verify Correct Configuration
- Upload a railway passenger regulation PDF. Check if the parsed text retains core fields such as regulation number and effective date. Confirm there is no content truncation or redundant page identifiers.
- Upload a Feishu service guide document with multi-level directories. Confirm the parsing result includes all hierarchical directory content and corresponding body paragraphs.
- Call the FastGPT v4.17.0 API to upload a test file. Check if the returned result contains complete parsed text, with no null values or timeout errors.
- View parsing logs in the backend. Confirm the
customPdfParseconfiguration item (if enabled) is correctly bound. Confirm parsing time falls within the range set byPARSE_FILE_TIMEOUT_SECONDS.
The values given 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.