LastCapacity (FIX tag 29)
LastCapacity (tag 29) is a char field defined in FIX 4.4 and FIX 4.2. It appears in 3 message types, always optionally. It is an enumerated field with 4 defined values.
At a glance
- Tag
- 29
- Name
- LastCapacity
- Datatype
- char
- Dialects
- FIX 4.4 and FIX 4.2
- Messages
- 3
- Valid values
- 4
What the specification says
Broker capacity in order execution
Descriptions are quoted from the FIX Orchestra sources under the Apache 2.0 licence.
A real message using tag 29
| Tag | Field | Wire value | Meaning |
|---|---|---|---|
| 8 | BeginString | FIX.4.4 | |
| 9 | BodyLength | 138 | |
| 35 | MsgType | 8 | Execution Report |
| 49 | SenderCompID | BOARTEAM | |
| 56 | TargetCompID | COUNTERPARTY | |
| 34 | MsgSeqNum | 2 | |
| 52 | SendingTime | 20240101-12:00:00.000 | |
| 37 | OrderID | ORD-10042 | |
| 17 | ExecID | EXEC-88117 | |
| 150 | ExecType | 0 | New |
| 39 | OrdStatus | 0 | New |
| 54 | Side | 1 | Buy |
| 29 | LastCapacity | 1 | Agent |
| 151 | LeavesQty | 0 | |
| 14 | CumQty | 1000000 | |
| 6 | AvgPx | 1.09215 | |
| 10 | CheckSum | 248 |
Shown with | separators for readability. On the wire FIX uses SOH (0x01), an invisible control byte — and because BodyLength and CheckSum are computed over the actual bytes, the two forms have different checksums. Both are valid and both decode here.
Generated from the FIX 4.4 dictionary and verified at build time: it parses and validates with no issues. Open the decoder to try your own message.
Valid values
A value outside this list is not a parse error — the message still decodes — but validate() reports it as validate/value-not-in-enum.
| Value | Meaning | Symbolic name |
|---|---|---|
| 1 | Agent | AGENT / Agent |
| 2 | Cross as agent | CROSS_AS_AGENT / CrossAsAgent |
| 3 | Cross as principal | CROSS_AS_PRINCIPAL / CrossAsPrincipal |
| 4 | Principal | PRINCIPAL / Principal |
Where tag 29 appears
Requiredness is a property of the message, not of the field: the same tag can be optional in one message and conditionally required in another.
| Message | MsgType | FIX 4.4 | FIX 4.2 | Where in the message |
|---|---|---|---|---|
| AllocationInstruction | J | Optional | Optional | inside the ExecAllocGrp component |
| AllocationReport | AS | Optional | — | inside the ExecAllocGrp component |
| ExecutionReport | 8 | Optional | Optional | directly on the message body |
Wire format
A single character. Most char fields are enumerated, so the value is one of a fixed set rather than arbitrary text. @boarteam/fix keeps the value as a string and, for enumerated fields, reports validate/value-not-in-enum when it is not a defined value.
Read tag 29 in TypeScript
import { createFixEngine } from "@boarteam/fix";import { dictionary } from "@boarteam/fix-dict-fix44";const fix = createFixEngine(dictionary);const { message, issues } = fix.parse(raw);const lastCapacity = message.fields[29]?.raw;// e.g. "1" — Agent// The dictionary also carries the labels:const label = fix.dictionary .fieldByTag(29) ?.enumValues?.find((e) => e.value === lastCapacity) ?.description;Other char fields
Decode this in your own code
The same engine that produced the decoded example above is an Apache-2.0 npm package with zero runtime dependencies. It runs in Node and in the browser, and parse() returns problems as data instead of throwing.
npm i @boarteam/fix @boarteam/fix-dict-fix44