# COBOL functions that answer questions about text A copybook and called programs over the C library, for GnuCOBOL. ## Install | Channel | Note | | --- | --- | | `thinkthen-cobol-VERSION-TARGET.tar.gz` | The copybook and the called programs, from each release. | | `thinkthen-c-VERSION-TARGET.tar.gz` | The C library it calls, from the same release. | Set `THINKTHEN_API_KEY` in the environment. ## A first call ``` identification division. program-id. first-call. environment division. configuration section. repository. function all intrinsic. data division. working-storage section. copy "thinkthen.cpy". 01 engine usage pointer. 01 question pic x(200). 01 question-length usage binary-double unsigned. 01 evidence pic x(200). 01 evidence-length usage binary-double unsigned. procedure division. call "thinkthen_engine_new" returning engine move "Does the customer ask for a refund?" to question move "Please refund my order. It arrived broken." to evidence perform ask-it if not outcome-yes stop run returning 1 end-if move '{"decide": "Does the customer ask ' & 'for a refund?", "threshold": "0.2:0.8"}' to question move "I want to send this back." to evidence perform ask-it if not outcome-not-sure stop run returning 1 end-if stop run returning 0. ask-it. move length(trim(question trailing)) to question-length move length(trim(evidence trailing)) to evidence-length call "TT-DECIDE" using engine question question-length evidence evidence-length tt-deadline-ms tt-answer tt-facts tt-failure. ``` *Build and run it beside the unpacked archives, thinkthen-c/ and thinkthen-cobol/* ``` cobc -x -free \ -fstatic-call -fno-gen-c-decl-static-call \ -I thinkthen-cobol/copybooks \ -A "-include $PWD/thinkthen-c/include/thinkthen.h \ -Wno-incompatible-pointer-types \ -Wno-implicit-function-declaration" \ -o first-call first-call.cob \ thinkthen-cobol/src/tt_decide.cob \ thinkthen-cobol/src/tt_error.cob \ -L thinkthen-c/lib -lthinkthen \ -Q "-Wl,-rpath,$PWD/thinkthen-c/lib" ./first-call ``` Not sure comes back as `outcome-not-sure`. Branch on it and send those cases to a person. ## Run facts `TT-DECIDE` fills `tt-facts` with this call's run facts as JSON text. `TT-JSON-MEMBER` reads one member. ## Errors `tt-failure` holds the kind as a code from 1 to 6, the retry flag and the message. Its level-88 names, such as `failure-backend`, test each kind. ## Settings and recording `TT-ENGINE-NEW` takes the settings as JSON. `"record"` writes a recording to a folder. `"replay"` answers from that recording with no connection. The [Settings](/install/settings/) page lists every setting. ## Jev, Liquid d1 and Ollama from COBOL COBOL reads its backend from the environment. Set `THINKTHEN_BACKEND` to the name below. Set the backend's key variable in the shell, and the same sample asks that backend. | Backend | Name | Key variable | | --- | --- | --- | | [TypeSafe Jev](/install/backends/typesafe/) | `typesafe` | `TYPESAFE_API_KEY` | | [Liquid d1](/install/backends/liquid/) | `liquid` | `LIQUIDAI_API_KEY`, then `LIQUID_API_KEY` | | [Ollama](/install/backends/ollama/) | `ollama` | `OLLAMA_API_KEY`. A local address needs no key. | *Ask TypeSafe Jev.* ``` export THINKTHEN_BACKEND=typesafe export TYPESAFE_API_KEY=... ``` *Ask Liquid d1.* ``` export THINKTHEN_BACKEND=liquid export LIQUIDAI_API_KEY=... ``` *Ask Ollama. This block names a second port, 11535, as the site's runs do. On the default port, leave THINKTHEN_BASE_URL out.* ``` export THINKTHEN_BACKEND=ollama export THINKTHEN_BASE_URL=http://localhost:11535/v1 ``` ``` identification division. program-id. backends. environment division. configuration section. repository. function all intrinsic. data division. working-storage section. copy "thinkthen.cpy". 01 engine usage pointer. 01 refund-question pic x(200) value "Does the customer ask for a refund?". 01 question pic x(200). 01 question-length usage binary-double unsigned. 01 evidence pic x(200). 01 evidence-length usage binary-double unsigned. procedure division. call "thinkthen_engine_new" returning engine move "Please refund my order. It arrived broken." to evidence perform ask-it if not outcome-yes stop run returning 1 end-if move "Thanks for the quick help yesterday!" to evidence perform ask-it if not outcome-no stop run returning 1 end-if stop run returning 0. ask-it. move refund-question to question move length(trim(question trailing)) to question-length move length(trim(evidence trailing)) to evidence-length call "TT-DECIDE" using engine question question-length evidence evidence-length tt-deadline-ms tt-answer tt-facts tt-failure. ``` *Build and run it beside the unpacked archives, thinkthen-c/ and thinkthen-cobol/* ``` cobc -x -free \ -fstatic-call -fno-gen-c-decl-static-call \ -I thinkthen-cobol/copybooks \ -A "-include $PWD/thinkthen-c/include/thinkthen.h \ -Wno-incompatible-pointer-types \ -Wno-implicit-function-declaration" \ -o backends backends.cob \ thinkthen-cobol/src/tt_decide.cob \ thinkthen-cobol/src/tt_error.cob \ -L thinkthen-c/lib -lthinkthen \ -Q "-Wl,-rpath,$PWD/thinkthen-c/lib" ./backends ``` The configuration file's `backend` names a default backend for every run. The [Configuration](/install/configuration/#configuration-file) page shows the file. ### OpenAI Decisions API from COBOL OpenAI announced its Decisions API on 2026-09-29 in its [DevDay 2026 recap](https://openai.com/index/devday-2026-recap/). OpenAI has published no address, schema or price, so ThinkThen cannot call it. The [OpenAI Decisions API](/install/backends/openai/) page says what ThinkThen knows. ## What is different in COBOL - Compile the programs you call from `src/` with your own, as the build line does with `TT-DECIDE`. - The copybook names no, yes and not sure as level-88 conditions, so `if outcome-yes` reads the answer. - `TT-DECIDE` writes into the question buffer, so set the question again before each call. On GitHub: [github.com/botassembly/thinkthen](https://github.com/botassembly/thinkthen)