[BOT ISSUE] Mistral: add deprecation markers for mistral-medium-2505 and mistral-medium-2508

[github-actions]

Summary

mistral-medium-2505 (Mistral Medium 3) and mistral-medium-2508 (Mistral Medium 3.1) were officially deprecated by Mistral on May 22, 2026, with a retirement date of August 31, 2026. The recommended replacement is Mistral Medium 3.5 (mistral-medium-3-5-26-04). Neither catalog entry has a deprecation_date field, so markModelsPastDeprecationDate() in models.ts will not auto-flag them and they continue appearing as active.

The mistral-medium-latest alias was already updated to point to Medium 3.5 pricing in a prior fix (#802), but the dated snapshots it replaced were never marked deprecated.

Affected Models

Model ID	Current deprecation_date	Correct Value	Deprecated	Retirement	Line
mistral-medium-2505	(missing)	2026-08-31	2026-05-22	2026-08-31	~4374
mistral-medium-2508	(missing)	2026-08-31	2026-05-22	2026-08-31	~4768

All other fields (pricing, format, provider) are correct and unchanged.

Verification

Check	Status	Detail
Cross-source (deprecation)	✅	Mistral models overview — Legacy/Deprecated section lists both with deprecation 5/22/2026 and retirement 8/31/2026
Replacement confirmed	✅	Official replacement is Mistral Medium 3.5 per same source
Already fixed	❌	Confirmed both entries lack deprecation_date in current model_list.json
Duplicate check	✅	No open issue covers these specific entries. Closed #802 fixed mistral-medium-latest pricing but did not add deprecation markers to dated snapshots

Verification Notes

Field	Source	Notes
Deprecation date 5/22/2026	Mistral models overview	Listed in Legacy/Deprecated table
Retirement date 8/31/2026	Mistral models overview	Both models share identical timeline
Replacement: Mistral Medium 3.5	Mistral models overview	Links to model card at /models/model-cards/mistral-medium-3-5-26-04

Local Files Inspected

• packages/proxy/schema/model_list.json — mistral-medium-2505 (line ~4374) and mistral-medium-2508 (line ~4768) both lack deprecation_date
• packages/proxy/schema/models.ts — markModelsPastDeprecationDate() (line ~217) checks deprecation_date to auto-set deprecated: true

{
  "kind": "stale_metadata",
  "provider": "mistral",
  "models": ["mistral-medium-2505", "mistral-medium-2508"],
  "status": "deprecated",
  "model_specs": {
    "mistral-medium-2505": {
      "format": "openai",
      "flavor": "chat",
      "multimodal": true,
      "input_cost_per_mil_tokens": 0.4,
      "output_cost_per_mil_tokens": 2,
      "parent": "mistral-medium-latest",
      "deprecation_date": "2026-08-31",
      "max_input_tokens": 131072,
      "max_output_tokens": 8191,
      "available_providers": ["mistral"]
    },
    "mistral-medium-2508": {
      "format": "openai",
      "flavor": "chat",
      "multimodal": true,
      "input_cost_per_mil_tokens": 0.4,
      "output_cost_per_mil_tokens": 2,
      "displayName": "Mistral Medium (2508)",
      "parent": "mistral-medium-latest",
      "deprecation_date": "2026-08-31",
      "max_input_tokens": 128000,
      "available_providers": ["mistral"]
    }
  },
  "source_urls": [
    "https://docs.mistral.ai/getting-started/models"
  ]
}

[github-actions]

Prepared catalog updates for mistral-medium-2505, mistral-medium-2508. Updated models: mistral-medium-2505, mistral-medium-2508.

Verification sources: https://docs.mistral.ai/getting-started/models
Verified metadata applied:

• mistral-medium-2505: format=openai, flavor=chat, parent=mistral-medium-latest, max_input_tokens=131072, max_output_tokens=8191, pricing(input/output per 1M)=0.4/2, providers=mistral, multimodal=true, deprecation_date=2026-08-31
• mistral-medium-2508: format=openai, flavor=chat, displayName=Mistral Medium (2508), parent=mistral-medium-latest, max_input_tokens=128000, max_output_tokens=not provided, pricing(input/output per 1M)=0.4/2, providers=mistral, multimodal=true, deprecation_date=2026-08-31

Included in the daily batch PR: #926