Tested prompt · AI email writer
A leaking tap, to the landlord: every AI model's reply, tested
We ran this everyday AI email writer test input on all 19 models in llmwise, the way the tool runs it, and checked every reply the same way. Here's each one as it came, with whether it passed, what it cost and how long it took.
Based on 19 of our test runs on , through OpenRouter with the tool's own instructions and the app's settings. Updated .
Short answer
All 19 models passed this AI email writer test input's check (key facts). The cheapest reply that passed was GPT-6 Luna's, at $0.000036; the fastest, GLM 5.3's in 0.8 s. The dearest reply, Claude Fable 5.1's, cost 385 times as much ($0.0140).
The prompt, as sent, and its check
Checked by key facts, the same way for every model.
A leaking tap, to the landlord (everyday)
Write this email for me, ready to send. Start with a line that starts "Subject:", and put anything you don't know in [brackets]. --- Tell my landlord, Mr. Okafor, that the kitchen tap in flat 4B has been leaking since 12 March and ask him to send a plumber this week. I'm home after 5:30 pm on weekdays.
Sent with the AI email writer's own instructions as the system prompt, as a free run of the tool sends them.
The answer must state “subject:”, “okafor”, “4b”, “12 march”, “5:30”, “plumber”.
How the AI email writer's test inputs are scored, with every model's results on all five.
Every model's result
All 19 models on this test input, in catalog order.
| Model | Result | Cost | Time | Reply |
|---|---|---|---|---|
| Claude Fable 5.1Anthropic | Passed: Stated all 6 facts with the section. | $0.0140 | 3.5 s | 181 tokens |
| Claude Opus 5.5Anthropic | Passed: Stated all 6 facts with the section. | $0.0056 | 2.4 s | 183 tokens |
| Claude Sonnet 5.5Anthropic | Passed: Stated all 6 facts with the section. | $0.0028 | 2.4 s | 184 tokens |
| Claude Sonnet 5Anthropic | Passed: Stated all 6 facts with the section. | $0.0026 | 2.7 s | 166 tokens |
| Claude Haiku 5.5Anthropic | Passed: Stated all 6 facts with the section. | $0.00016 | 1.7 s | 225 tokens |
| Claude Haiku 4.5Anthropic | Passed: Stated all 6 facts with the section. | $0.0010 | 1.6 s | 130 tokens |
| GPT-6 AstraOpenAI | Passed: Stated all 6 facts with the section. | $0.0040 | 2.5 s | 86 tokens |
| GPT-6.1 SolOpenAI | Passed: Stated all 6 facts with the section. | $0.00083 | 2.1 s | 92 tokens |
| GPT-6 SolOpenAI | Passed: Stated all 6 facts with the section. | $0.00073 | 2.9 s | 73 tokens |
| GPT-6 LunaOpenAI | Passed: Stated all 6 facts with the section. | $0.000036 | 1.0 s | 72 tokens |
| Gemini 3.1 Pro (preview)Google | Passed: Stated all 6 facts with the section. | $0.0050 | 7.3 s | 116 tokens |
| Gemini 3.8 FlashGoogle | Passed: Stated all 6 facts with the section. | $0.00035 | 2.5 s | 108 tokens |
| DeepSeek V4.1 FlashDeepSeek | Passed: Stated all 6 facts with the section. | $0.00030 | 1.0 s | 125 tokens |
| DeepSeek V4 ProDeepSeek | Passed: Stated all 6 facts with the section. | $0.0020 | 4.8 s | 92 tokens |
| Grok 4.7xAI | Passed: Stated all 6 facts with the section. | $0.0041 | 7.0 s | 73 tokens |
| Kimi K3Moonshot | Passed: Stated all 6 facts with the section. | $0.0016 | 2.0 s | 107 tokens |
| GLM 5.3Z.ai | Passed: Stated all 6 facts with the section. | $0.00088 | 0.8 s | 101 tokens |
| GLM 5.3 FlashZ.ai | Passed: Stated all 6 facts with the section. | $0.00011 | 1.7 s | 102 tokens |
| Mistral Large 4Mistral | Passed: Stated all 6 facts with the section. | $0.0083 | 101.5 s | 309 tokens |
Cost: what OpenRouter charged us for the reply. Time: from sending to the whole reply. Reply: its length in tokens, thinking not counted. In llmwise you pay per message, not per token: each of these replies counted as one message on Pro.
Every reply
Every reply passed: here they are from the cheapest up.
GPT-6 Luna
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B Dear Mr. Okafor, I’m writing to report that the kitchen tap in flat 4B has been leaking since 12 March. Could you please send a plumber this week? I’m home after 5:30 pm on weekdays. Best, [your name]
367 tokens in, 72 out · 1.0 s · $0.0000 · 1 message on Pro · answered by openai/gpt-6-luna via OpenAI ·
GLM 5.3 Flash
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B – plumber needed Dear Mr. Okafor, I am writing to report a leaking kitchen tap in flat 4B. The tap has been leaking since 12 March and it still needs attention. Could you please arrange for a plumber to come this week? I am home after 5:30 pm on weekdays, so any weekday visit after that time would work well. Thank you for your help. Kind regards, [Your name]
381 tokens in, 102 out · 1.7 s · $0.0001 · 1 message on Pro · answered by z-ai/glm-5.3-flash via Friendli ·
Claude Haiku 5.5
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B, repair needed this week Dear Mr. Okafor, I am writing to report that the kitchen tap in flat 4B has been leaking since 12 March. The leak is ongoing and I would be grateful if you could arrange for a plumber to attend this week. I am at home after 5:30 pm on weekdays, so please let me know a suitable time within those hours, or [alternative access arrangement, if any]. You can reach me on [your phone number] or by replying to this email. Thank you for your help with this. I look forward to hearing from you. Kind regards, [your name] Flat 4B [your address, if needed]
493 tokens in, 225 out · 1.7 s · $0.0002 · 1 message on Pro · answered by anthropic/claude-haiku-5.5 via Anthropic ·
DeepSeek V4.1 Flash
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B — plumber needed this week Dear Mr. Okafor, I'm writing to report a problem with the kitchen tap in flat 4B. It has been leaking since 12 March, and I'd be grateful if you could send a plumber this week to look at it. I'm home after 5:30 pm on weekdays, so any visit in the evening would suit me. Please let me know when the plumber can come. Kind regards, [your name] [flat 4B, your phone number or email]
402 tokens in, 150 out (25 of them reasoning) · 1.0 s · $0.0003 · 1 message on Pro · answered by deepseek/deepseek-v4.1-flash via Together ·
Gemini 3.8 Flash
Passed: Stated all 6 facts with the section.
Subject: Repair request: Leaking kitchen tap in flat 4B Dear Mr. Okafor, I am writing to report that the kitchen tap in flat 4B has been leaking since 12 March. Could you please arrange for a plumber to inspect and fix it this week? I am available at home after 5:30 pm on weekdays to grant access. Please let me know when someone might be able to come by. Best regards, [Your Name] [Your Phone Number]
389 tokens in, 108 out · 2.5 s · $0.0003 · 1 message on Pro · answered by google/gemini-3.8-flash via Google AI Studio ·
GPT-6 Sol
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B Dear Mr. Okafor, I’m writing about the kitchen tap in flat 4B, which has been leaking since 12 March. Could you please send a plumber this week? I’m home after 5:30 pm on weekdays. Thank you, [your name]
367 tokens in, 73 out · 2.9 s · $0.0007 · 1 message on Pro · answered by openai/gpt-6-sol via OpenAI ·
GPT-6.1 Sol
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B Dear Mr. Okafor, The kitchen tap in flat 4B has been leaking since 12 March. Could you please send a plumber this week to repair it? I’m home after 5:30 pm on weekdays and can provide access then. Please let me know when the plumber will be coming. Thank you for your help. Kind regards, [your name]
367 tokens in, 92 out · 2.1 s · $0.0008 · 1 message on Pro · answered by openai/gpt-6.1-sol via OpenAI ·
GLM 5.3
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B Dear Mr. Okafor, I'm writing to report a maintenance issue in my flat. The kitchen tap in flat 4B has been leaking since 12 March, and I would appreciate it if you could send a plumber this week to fix it. I'm home after 5:30 pm on weekdays, so any appointment after that time would work well. Thank you for your help. Best regards, [your name]
381 tokens in, 101 out · 0.8 s · $0.0009 · 1 message on Pro · answered by z-ai/glm-5.3 via Friendli ·
Claude Haiku 4.5
Passed: Stated all 6 facts with the section.
Subject: Urgent: Kitchen Tap Leak in Flat 4B Dear Mr. Okafor, I am writing to report a leak in the kitchen tap of flat 4B, which has been ongoing since 12 March. This requires urgent attention. Could you please arrange for a plumber to visit this week to repair it? I am home after 5:30 pm on weekdays and available at [your preferred phone number] if the plumber needs to confirm a time. Thank you for your prompt attention to this matter. Best regards, [Your name]
391 tokens in, 130 out · 1.6 s · $0.0010 · 1 message on Pro · answered by anthropic/claude-haiku-4.5 via Anthropic ·
Kimi K3
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B – plumber needed Dear Mr. Okafor, I'm writing to let you know that the kitchen tap in flat 4B has been leaking since 12 March. Could you please arrange for a plumber to come and fix it this week? I'm home after 5:30 pm on weekdays, so any evening appointment would work for me. Thank you for your help. Best regards, [Your name] Flat 4B
454 tokens in, 127 out (20 of them reasoning) · 2.0 s · $0.0016 · 1 message on Pro · answered by moonshotai/kimi-k3 via Wafer ·
DeepSeek V4 Pro
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B Dear Mr. Okafor, I am writing to report that the kitchen tap in flat 4B has been leaking since 12 March and to ask you to send a plumber this week. I am home after 5:30 pm on weekdays, so a plumber could visit then. Please let me know if you need any further details. Kind regards, [Your name]
376 tokens in, 469 out (377 of them reasoning) · 4.8 s · $0.0020 · 1 message on Pro · answered by deepseek/deepseek-v4-pro-0813 via Wafer ·
Claude Sonnet 5
Passed: Stated all 6 facts with the section.
Subject: Leaking Kitchen Tap in Flat 4B – Request for Plumber Dear Mr. Okafor, I'm writing to report that the kitchen tap in flat 4B has been leaking since 12 March. Could you please arrange for a plumber to come and fix it this week? I am home after 5:30 pm on weekdays, so any visit during that time would work well for me. Thank you for your prompt attention to this matter. Best regards, [your name] Flat 4B
491 tokens in, 166 out · 2.7 s · $0.0026 · 1 message on Pro · answered by anthropic/claude-sonnet-5 via Anthropic ·
Claude Sonnet 5.5
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B – plumber needed this week Dear Mr. Okafor, I'm writing to report that the kitchen tap in flat 4B has been leaking since 12 March. I would be grateful if you could arrange for a plumber to visit this week. I'm home after 5:30 pm on weekdays, so any evening from Monday to Friday would suit me. Please let me know which day the plumber will come. Thank you for your help. Kind regards, [your name] Flat 4B [your phone number]
493 tokens in, 184 out · 2.4 s · $0.0028 · 1 message on Pro · answered by anthropic/claude-sonnet-5.5 via Anthropic ·
GPT-6 Astra
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B Dear Mr. Okafor, The kitchen tap in flat 4B has been leaking since 12 March. Could you please send a plumber this week to repair it? I'm home after 5:30 pm on weekdays. Please let me know which day the plumber can come. Thank you for your help. Kind regards, [your name]
367 tokens in, 86 out · 2.5 s · $0.0040 · 1 message on Pro · answered by openai/gpt-6-astra via OpenAI ·
Grok 4.7
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B Dear Mr. Okafor, I am writing to tell you that the kitchen tap in flat 4B has been leaking since 12 March. I am asking you to send a plumber this week. I am home after 5:30 pm on weekdays. Thank you, [your name]
1,605 tokens in, 433 out (360 of them reasoning) · 7.0 s · $0.0041 · 1 message on Pro · answered by x-ai/grok-4.7 via xAI ·
Gemini 3.1 Pro
Passed: Stated all 6 facts with the section.
Subject: Maintenance request for flat 4B Dear Mr. Okafor, I am writing to report a maintenance issue in flat 4B. The kitchen tap has been leaking since 12 March, and it needs to be repaired. Could you please send a plumber this week to fix the leak? I am home after 5:30 pm on weekdays, so any time after that would be perfect for me to let them in. Please let me know when someone is scheduled to come by. Best regards, [Your Name]
389 tokens in, 774 out (658 of them reasoning) · 7.3 s · $0.0050 · 1 message on Pro · answered by google/gemini-3.1-pro-preview via Google AI Studio ·
Claude Opus 5.5
Passed: Stated all 6 facts with the section.
Subject: Leaking Kitchen Tap in Flat 4B – Plumber Needed This Week Dear Mr. Okafor, I'm writing to let you know that the kitchen tap in flat 4B has been leaking since 12 March. Could you please arrange for a plumber to come and repair it this week? I'm home after 5:30 pm on weekdays, so any visit after that time would work well for me. Please let me know when the plumber is scheduled to come. Thank you for your help. Kind regards, [your name] [your phone number]
493 tokens in, 183 out · 2.4 s · $0.0056 · 1 message on Pro · answered by anthropic/claude-opus-5.5 via Google ·
Mistral Large 4
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B Dear Mr. Okafor, I am writing to report that the kitchen tap in flat 4B has been leaking since 12 March and to ask you to send a plumber this week. I am home after 5:30 pm on weekdays if you need to arrange a visit. Thank you for your help. Best regards, [your name]
377 tokens in, 3,840 out (3,531 of them reasoning) · 101.5 s · $0.0083 · 1 message on Pro · answered by mistralai/mistral-large-4-0 via Mistral ·
Claude Fable 5.1
Passed: Stated all 6 facts with the section.
Subject: Leaking kitchen tap in flat 4B – plumber needed this week Dear Mr. Okafor, I am writing to report that the kitchen tap in flat 4B has been leaking since 12 March. Could you please arrange for a plumber to come and repair it this week? I am home after 5:30 pm on weekdays, so any time after that would suit me. Please let me know the date and time once it is booked so I can be in. Thank you for your help with this. Kind regards, [your name] Flat 4B [your phone number]
493 tokens in, 181 out · 3.5 s · $0.0140 · 1 message on Pro · answered by anthropic/claude-fable-5.1 via Google ·
More AI email writer test inputs
The other AI email writer test inputs, each with every model's reply, and the results across all five.
Questions
Which AI does best on “A leaking tap, to the landlord”?
All 19 models passed this AI email writer test input's check (key facts). The cheapest reply that passed was GPT-6 Luna's, at $0.000036; the fastest, GLM 5.3's in 0.8 s. The dearest reply, Claude Fable 5.1's, cost 385 times as much ($0.0140).
What does a reply to “A leaking tap, to the landlord” cost?
Through the models' APIs, what OpenRouter charged us ran from $0.000036 (GPT-6 Luna) to $0.0140 (Claude Fable 5.1) for this test input. In llmwise you don't pay by the token: a reply like these counts as one message on Pro, whichever model answers.
Claude, GPT, Gemini, DeepSeek, Grok, Kimi, GLM, and Mistral, in one chat.
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