Verified rather than adopted: a subagent proposed that every even operand slot is a type tag. Measured, the strong form is false and a precise form is true. TRUE: a SYMBOL operand is two words, a tag holding the constant 1 followed by the index. Slot 0 is the integer 1 in 19899/19899 calls whose slot 4 is a unit; slot 8 is tag-shaped in 100% of calls for every built-in taking a second unit; slot 16 is 1 in 152/152 for built-in 128, the only one taking a third. The 24 built-ins whose slot 0 is NOT the constant are exactly those taking no symbol there. This explains the unit slots 4/12/20 rather than replacing them. FALSE as stated: slot 8 is a bare double for built-ins 4, 20, 24, 26, 28, 29, 90, 106 and 127, and built-in 75 carries five bare indices at 0/4/8/12/16 with no tags at all. Each built-in has a fixed signature and is 100% self-consistent; none of the 34 with >=20 sites mixes the two. Symbol table 1 has three types -- 1 routes (1362), 6 messages (2247), 7 effects (81) -- and its operand slots are type-pure, measured the same way. Resolving them makes listings say what the script means: `request_script_message(MSG_VOICE_D_257, ...)`, a fourth independent confirmation of that name. Slots 24@4, 46@12 and 114@4 resolve 100% but MIX types 6 and 1, so they are left unresolved rather than guessed. Two more names withdrawn, neither replaced: * 88 `camera_at` -- ZERO call sites in all 28 stages; never testable. * 90 `camera_at_route` -- 8 sites, all Stage 02 phase 3, first operand is symtab-1 type 7 `eff_n0071`, an EFFECT name, in 8/8, with a per-missile Route_ADT301..308_p3M at slot 20. Not aimed at a camera. Left unnamed on purpose: replacing a guessed name with another guess is how the three names corrected earlier today went wrong. Also flagged: 115 `named_event`'s only symbol operand is an eff_* name in 84/84 sites, so that name is suspect too. Not renamed pending a handler read. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01PMRJjbxLqZtsb5Vb7KunPE