Short answer. If the initial conference does not resolve the petition, Article 246 of the Family Code sends it to a summary hearing decided on affidavits, documentary evidence, or oral testimony at the court's discretion, not a full trial. If testimony is needed, the court itself specifies which witnesses and what subjects they must address.
What the law says
If the petition is not resolved at the initial conference, said petition shall be decided in a summary hearing on the basis of affidavits, documentary evidence or oral testimonies at the sound discretion of the court. If testimony is needed, the court shall specify the witnesses to be heard and the subject-matter of their testimonies, directing the parties to present said witnesses.
Family Code, Article 246 — Summary Hearing on Affidavits and Evidence. Read the full provision →
The default path is summary, not a full trial
Article 246 answers this directly: if the petition is not resolved at the initial conference, said petition shall be decided in a summary hearing on the basis of affidavits, documentary evidence or oral testimonies at the sound discretion of the court. That is a materially lighter process than an ordinary civil trial — the court is empowered to decide the matter from written evidence and sworn statements rather than running a full-blown adversarial proceeding with the customary trial calendar.
The court decides whether testimony is even needed
Nothing in this provision guarantees you a hearing with live witnesses. Whether oral testimony features at all is left at the sound discretion of the court — the judge may decide the affidavits and documents on file are sufficient to resolve the petition without calling anyone to the stand. So "summary hearing" here does not necessarily mean a hearing in the everyday sense of witnesses being examined; it can mean a decision made on the papers.
When testimony is required, the court controls its scope
If the court does decide testimony is needed, Article 246 puts the court in charge of shaping it: the court shall specify the witnesses to be heard and the subject-matter of their testimonies, directing the parties to present said witnesses. This is narrower than the open-ended witness examination typical of a full trial — the judge defines in advance who will be heard and on what subject, and the parties are directed to produce those specific witnesses rather than mounting a wide-ranging presentation of their own choosing.
What this means for how you prepare
Because the proceeding can be decided on affidavits and documents alone, the strength of your written evidence matters as much as, or more than, anything you might say in person. Gather and organize whatever documentary evidence supports your petition before the initial conference, and treat your affidavit as the primary vehicle for your account of the facts, since the court may never call you to testify beyond what that written record already shows.