Skills

Spellcraft (Int; Trained Only)

Use this skill to identify spells as they are cast or spells already in place.

Spellcraft DC
Task
13
When using read magic, identify a glyph of warding. No action required.
15 + spell level
Identify a spell being cast. (You must see or hear the spell's verbal or somatic components.) No action required. No retry.
15 + spell level
Learn a spell from a spellbook or scroll (wizard only). No retry for that spell until you gain at least 1 rank in Spellcraft (even if you find another source to try to learn the spell from). Requires 8 hours.
15 + spell level
Prepare a spell from a borrowed spellbook (wizard only). One try per day. No extra time required.
15 + spell level
When casting detect magic, determine the school of magic involved in the aura of a single item or creature you can see. (If the aura is not a spell effect, the DC is 15 + one-half caster level.) No action required.
19
When using read magic, identify a symbol. No action required.
20 + spell level
Identify a spell that's already in place and in effect. You must be able to see or detect the effects of the spell. No action required. No retry.
20 + spell level
Identify materials created or shaped by magic, such as noting that an iron wall is the result of a wall of iron spell. No action required. No retry.
20 + spell level
Decipher a written spell (such as a scroll) without using read magic. One try per day. Requires a full-round action.
25 + spell level
After rolling a saving throw against a spell targeted on you, determine what that spell was. No action required. No retry.
25
Identify a potion. Requires 1 minute. No retry.
20
Draw a diagram to allow dimensional anchor to be cast on a magic circle spell. Requires 10 minutes. No retry. This check is made secretly so you do not know the result.
30 or higher
Understand a strange or unique magical effect, such as the effects of a magic stream. Time required varies. No retry.

You can identify spells and magic effects. The DCs for Spellcraft checks relating to various tasks are summarized on the table above.

Action: Varies, as noted above.

Try Again: See above.

Special: If you are a specialist wizard, you get a +2 bonus on Spellcraft checks when dealing with a spell or effect from your specialty school. You take a -5 penalty when dealing with a spell or effect from a prohibited school (and some tasks, such as learning a prohibited spell, are just impossible).

If you have the Magical Aptitude feat, you get a +2 bonus on Spellcraft checks.

Synergy: If you have 5 or more ranks in Knowledge (arcana), you get a +2 bonus on Spellcraft checks.

If you have 5 or more ranks in Use Magic Device, you get a +2 bonus on Spellcraft checks to decipher spells on scrolls.

If you have 5 or more ranks in Spellcraft, you get a +2 bonus on Use Magic Device checks related to scrolls.

Additionally, certain spells allow you to gain information about magic, provided that you make a successful Spellcraft check as detailed in the spell description.

Epic Use

The character can identify properties of a magic item.

DC
Task
50 + caster level
Identify basic property of magic item
70 + caster level
Identify all properties of magic item
50
Quick identification of alchemical substances and potions

Identify Basic Property of Magic Item: This use of the skill requires one round of inspection, and functions exactly as if the character had cast an identify spell on the item. A character can't attempt this on the same item more than once.

Identify All Properties of Magic Item: This requires one minute of inspection, and reveals all properties of a single magic item (including command words and charges remaining). A character can't attempt this on the same item more than once. If an item has different caster levels for different properties, use the highest caster level.

Quick Identification: A character can identify a substance or potion in the field as a full-round action, without an alchemical lab or any cost. The character can't retry this check (or take 20); if he or she fails, the character must identify the substance in an alchemical lab, as normal.

Source: SRD 3.5 Combined Skills