Commission a report: this endpoint runs many searches and writes a long, cited document. `model` (required, `sonar-deep-research`) and `messages` in; `choices[0].message.content`, `citations`, `search_results[]` and `usage` out, where `usage` also reports `num_search_queries` and `reasoning_tokens`. ⚠️ Budget for the wait: a two-sentence question measured **192 seconds** and returned 86 KB after 10 upstream searches — roughly 60 times slower and 10 times larger than `post_perplexity_sonar`, at the same flat $0.012 per request. Many clients time out well before it answers, so call it only when a report is genuinely the deliverable, and never in a loop. For anything you would read in one sitting, the other three Perplexity endpoints answer in seconds.