Error code reference

Each FloxError carries a stable code (e.g. E_SYM_001), a human message, and a help URL pointing to the per-code page in this section. AI agents reading FLOX errors can resolve the code to a documented fix without parsing free-text messages.

Code format

E_<DOMAIN>_<NUMBER> — DOMAIN is a short uppercase tag identifying the subsystem; NUMBER is a zero-padded 3-digit counter within that domain. Codes never change meaning once published; if the cause shifts, a new code is allocated.

Domain	Subsystem
SYM	Symbol registry / lookups
DATA	Input data loading and parsing
KEY	Event field lookups and required keys
TIME	Calendar, intervals, timestamps
LEN	Array length mismatches
ORDER	Order submission and lifecycle
RISK	Pre-trade risk hooks
IDX	Index out of range
IO	Filesystem and binary log I/O
CONFIG	Configuration validation

Catalog

Code	Message
E_SYM_001	Symbol is not registered
E_RUN_003	Invalid factory return value (GridSearch)

How to add a new code

1. Decide on a domain. If a new domain is needed, add it to the table above.
2. Pick the next number in that domain.
3. Write a Markdown page docs/errors/<code>.md with the frontmatter shown below.

4. Use the code at the throw site:

   throw flox::FloxError(
       "E_SYM_001",
       "Symbol '" + name + "' is not registered. ...");
   

5. Run python3 scripts/check_error_codes.py (it also runs in CI). It verifies every code referenced from source has a Markdown page and vice-versa.

Frontmatter convention

---
code: E_SYM_001
title: Symbol is not registered
severity: error
since: 0.1.0
---