Teachers increasingly configure educational chatbots through natural-language instructions, but how these bots fail in real-world use remains poorly understood. We introduce EduWild, a dataset of 1,726 conversations with 217 teacher-configured chatbots, each paired with the instructions and configuration behind it, including 900 conversations from the intended end users of 35 deployed chatbots. We develop a 29-code taxonomy covering factual, workflow, diagnostic, and pedagogical failures and apply it using a human-calibrated LLM judge. The most frequent failures are lapses in following teacher intent --- bots skip required workflow steps (53.8% of end-user conversations), omit expectation setup (33.4%), and overload learners with information or questions (37.1%). Guided by these findings, we design a prompt-based harness targeting the six most frequent failure modes. In a study with 200 college students across ten bots, the harness reduces the mean number of target failure codes per conversation from 1.406 to 0.489, a 65.2% relative reduction with bots weighted equally. These findings show how real-world failure analysis can guide practical improvements to educational chatbots.
Figures & tables
All
Deployed
Overview
Chatbots
217
35
Educators
85
15
Chatbots per educator †
1
2
Prompt length (words) †
296
500
Configuration
Table 1: Authoring data for all and deployed chatbots. † Median. ‡ Configured at export.
Dataset
Domain
Tutor
Real-world deployment data
Authoring data
Dialogues
TutorChat
STEM
LLM (synthetic)
✗
✗
80,000
SocraTeach
Math
LLM (synthetic)
✗
✗
35,000
EduDial
Math
LLM (synthetic)
✗
✗
34,250
MathDial
Math
Human teacher
✗
✗
2,861
CIMA
Language
Crowdworker
✗
✗
391
TSCC
Language
Human teacher
✓
✗
260
Table 2: Comparison with existing tutoring and user-chatbot dialogue datasets. Real-world deployment: conversations with intended users. Authoring data: paired with the teacher’s system prompt, configuration, and test conversations.
Figure 1: Conversation-level prevalence of all 29 failure codes, grouped by taxonomy category and sorted by prevalence within each category. Saturated bars mark the six codes above 10% of conversations (dashed line) that the harness targets (§ 5.1 ); colours follow Figure 2 . Each percentage uses all 900 conversations as the denominator. Code definitions appear in Appendix B .
Category
Codes
Theoretical Grounding
Factual (F1–F7) The bot gives wrong, incomplete, inconsistent, or ungrounded content, or oversteps or misapplies the prompt’s boundaries.
LearnLM; MathDial; ICAP ( Chi and Wylie, 2014 ) ; KLI ( Koedinger et al., 2012 )
Table 3: Taxonomy of failure modes in teacher-configured educational chatbots. Full definitions and examples are listed in Appendix B .
Figure 2: Harness architecture. (a) An LLM extracts teacher intent into persistent memory. (b) The tutor opens with a brief self-introduction. (c) Each response uses the original teacher prompt, six failure-specific prompts, cached teacher intent, and dialogue history.
Prevalence (%)
Relative
Code
Failure
Harness prompt objective
Control
Harness
reduction (%)
95% CI
W7
Skipped or missing structure
Follow the teacher’s workflow and build on completed learner contributions.
43.9
32.2
26.7
[−21.7,−1.5]
W9
No expectation setup
Establish the bot’s role, scope, and interaction style at opening.
6.9
0.9
86.8
[−11.1,−1.2]
P3
Cognitive overload
Keep information manageable and pace broad tasks across turns.
39.7
7.6
80.9
[−40.1,−23.9]
W6
Multi-question overload
Request one learner contribution at a time and follow up on necessary unanswered questions.
27.7
1.1
96.0
[−33.8,−19.3]
F5
Guardrail breach
Respect the teacher’s task boundaries, permissions, and exceptions.
12.1
5.0
58.6
[−13.2,−1.0]
Table 4: Harness prompts and their effects in the participant study (100 participants per condition). Each row pairs a target failure code with the objective of the prompt that addresses it. Codes are ordered by prevalence in the corpus. Rates weight each of the ten bots equally; reduction is relative to the control rate. CIs describe harness minus control, in percentage points for prevalence and in codes for means.
Figure 3: Authoring data. (a) Example chatbot record. (b) Playlab authoring interface for the same chatbot: start screen (left), system-prompt editor (center), and attached references (right). The chatbot name shown ( Art Detective ) is a placeholder chosen to reflect the chatbot’s purpose; the original name is withheld for anonymity.
Figure 4: Interaction data. (a) Example conversation record with its first three messages. (b) End-user chat view of the same chatbot. The chatbot name shown ( Art Detective ) is a placeholder chosen to reflect the chatbot’s purpose; the original name is withheld for anonymity.
Appendix figures & tables2 assets
Supplementary material from the paper’s appendix.
Appendix
End users
Authors
Others
Total
Users
900 ∗
74
42
993 ∗
Chatbots
35
177
58
182
Conversations
900
741
85
1,726
Messages
10,461
6,861
660
17,982
Messages / conv. †
7
7
5
7
User msgs / conv. †
3
3
2
3
Appendix
Table 5: Interaction data by user group. Others: other educators in the same program. † Median. ∗ End users accessed chatbots anonymously, so each conversation is counted as one user; the total counts 900 end-user conversations plus 93 distinct educators (some of them did not build chatbots).
Figure 5: Prolific task interface. Left: Step 1 scenario card with course material and comprehension check. Right: Step 2 chatbot link and completion criteria.
Department of Mechanical Engineering, Imperial College London, UK · Department of Electrical Engineering, Imperial College London, UK · Department of Earth Science and Engineering, Imperial College London, UK