[Bug] Claude repeatedly fabricates information in complex tasks despite acknowledgment

Bug Description
Opus 4.7 is consistentley making stuff up to try to get out of a complext problem, and a single message facing him with his acts makes him apologise and acknowledge with 0 behavioral change as he will keep making stuff up in the very next message, very wierd behavior

Environment Info

• Platform: darwin
• Terminal: Apple_Terminal
• Version: 2.1.114
• Feedback ID: f1173adc-9ca7-4a3c-b671-0f59708cc2a2

Errors

[{"error":"McpToolCallError: Error executing tool disassemble_function: 1 validation error for disassemble_functionArguments\naddress\n  Field required [type=missing, input_value={'name': 'FUN_18053c280'}, input_type=dict]\n    For further information visit https://errors.pydantic.dev/2.13/v/missing\n    at CJ7 (/$bunfs/root/src/entrypoints/cli.js:4759:63)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-20T02:38:44.182Z"},{"error":"Error: ripgrep exited with code null\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:676:946)\n    at emit (node:events:98:22)\n    at #maybeClose (node:child_process:766:16)\n    at #handleOnExit (node:child_process:520:72)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-20T02:51:00.212Z"},{"error":"RipgrepTimeoutError: Ripgrep search timed out after 20 seconds. The search may have matched files but did not complete in time. Try searching a more specific path or pattern.\n    at T (/$bunfs/root/src/entrypoints/cli.js:679:242)\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:679:456)\n    at <anonymous> (/$bunfs/root/src/entrypoints/cli.js:676:1017)\n    at emit (node:events:98:22)\n    at #maybeClose (node:child_process:766:16)\n    at #handleOnExit (node:child_process:520:72)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-20T02:51:00.213Z"},{"error":"Error: Request was aborted.\n    at makeRequest (/$bunfs/root/src/entrypoints/cli.js:50:3448)\n    at processTicksAndRejections (native:7:39)","timestamp":"2026-04-20T02:56:46.605Z"},{"error":"Error: ensureToolResultPairing: repaired missing tool_result blocks (552 -> 552 messages). Message structure: [0] user; [1] user; [2] assistant(id=msg_01FHQLEDsCrdKLJquVB6PVbr, tool_uses=[toolu_01Fh1DRkqWZHDS8NgLhGZm6r,toolu_01N4isGneyNhp431zfgMKd1d,toolu_017tNrchcyDzkb6mePoburpW]); [3] user(tool_results=[toolu_01Fh1DRkqWZHDS8NgLhGZm6r,toolu_01N4isGneyNhp431zfgMKd1d,toolu_017tNrchcyDzkb6mePoburpW]); [4] assistant(id=msg_017xf3ipNkftrc54Yn65p5Sb, tool_uses=[toolu_01HoG2ig4nY9cvG6LagaQNGc,toolu_01WnGnkN97J6kvS35igFj8q1,toolu_01SM5QpcgDzNHcKFryzURVcP]); [5] user(tool_results=[toolu_01HoG2ig4nY9cvG6LagaQNGc,toolu_01WnGnkN97J6kvS35igFj8q1,toolu_01SM5QpcgDzNHcKFryzURVcP]); [6] assistant(id=msg_01SMTtwRjzEBhxdSPkQ8CTwS, tool_uses=[toolu_0161FMwrJP8AhmdiMP39YBvr]); [7] user(tool_results=[toolu_0161FMwrJP8AhmdiMP39YBvr]); [8] assistant(id=msg_01LwfMBuKKTR2DvGxTNjMeVg, tool_uses=[toolu_01Jfd84VNPYwyJ3RVHUrKNEw]); [9] user(tool_results=[toolu_01Jfd84VNPYwyJ3RVHUrKNEw]); [10] assistant(id=msg_01UqdbF4NY8Do4Byy1NrbNUP, tool_uses=[toolu_016Nrx8nqtyJwCRaufhPgdgg]); [11] user(tool_results=[toolu_016Nrx8nqtyJwCRaufhPgdgg]); [12] assistant(id=msg_018JjUemmcWCELrEDRAsX3pB, tool_uses=[toolu_012Tnja8f5dX9gVFgyYmDhxk]); [13] user(tool_results=[toolu_012Tnja8f5dX9gVFgyYmDhxk]); [14] assistant(id=msg_01K5DqAXqyQQeEAapnhNwo67, tool_uses=[toolu_01Lr2qjFEsq8o15X71FGV1V4]); [15] user(tool_results=[toolu_01Lr2qjFEsq8o15X71FGV1V4]); [16] assistant(id=msg_01K7G7pVNXJkzW31CtdPt7cP, tool_uses=[toolu_01UR4fcKp1jiF3y7CimKugeZ]); [17] user(tool_results=[toolu_01UR4fcKp1jiF3y7CimKugeZ]); [18] assistant(id=msg_018QyStBuPbBNsgMUpy7modg, tool_uses=[toolu_0183kSJHgvHNKENV5F8Vvjte,toolu_01FbEKf1xmuMyHePhcdAzAAn]); [19] user(tool_results=[toolu_0183kSJHgvHNKENV5F8Vvjte,toolu_01FbEKf1xmuMyHePhcdAzAAn]); [20] assistant(id=msg_01AQ5kLoqapNx417KEoDMR3c, tool_uses=[toolu_01JSRmfaU8E9t6PV97V3fMSt]); [21] user(tool_results=[toolu_01JSRmfaU8E9t6PV97V3fMSt]); [22] assistant(id=msg_012fq7H18SpQAQH9mMat9YqM, tool_uses=[toolu_01UXyCiFu3U4VSjErnL6rnwf]); [23] user(tool_results=[toolu_01UXyCiFu3U4VSjErnL6rnwf]); [24] assistant(id=msg_015yAxeLSEBXYM7rANuMt51G, tool_uses=[toolu_01MVNyQzgbxgU6DHdZQ4wBpa]); [25] user(tool_results=[toolu_01MVNyQzgbxgU6DHdZQ4wBpa]); [26] assistant(id=msg_0177ohF5mRkxD398kPpvg7Qm, tool_uses=[toolu_01Wnus9CRkfugEKxseJEL31B,toolu_01AuyBRAcHdqt1XPiCfG9ym5]); [27] user(tool_results=[toolu_01Wnus9CRkfugEKxseJEL31B,toolu_01AuyBRAcHdqt1XPiCfG9ym5]); [28] assistant(id=msg_01JEmC8AFbdDTUef67jZaQdH, tool_uses=[]); [29] user; [30] assistant(id=msg_013atDRKFaYVWFmrbkeTxY4u, tool_uses=[]); [31] user; [32] assistant(id=msg_01Hap1PtGwQyrnEpkiJBnzYn, tool_uses=[toolu_011sYWpBiJA6SPhZFFFQ7qfN]); [33] user(tool_results=[toolu_011sYWpBiJA6SPhZFFFQ7qfN]); [34] assistant(id=msg_0121JJSc6FA7zjKRaf6qoSRL, tool_uses=[toolu_01QbxxW6B8bTY1ctmCWoTK2g]); [35] user(tool_results=[toolu_01QbxxW6B8bTY1ctmCWoTK2g]); [36] assistant(id=msg_01FJ7mgWVRMHWFqaCaH5rLyj, tool_uses=[toolu_019GtyvEZzPPF58G6Ua512Qs]); [37] user(tool_results=[toolu_019GtyvEZzPPF58G6Ua512Qs]); [38] assistant(id=msg_01YRDAh7jCR69FbCTnkgcYB2, tool_uses=[toolu_019u76umZKpRPUFCWWVaiRuq]); [39] user(tool_results=[toolu_019u76umZKpRPUFCWWVaiRuq]); [40] assistant(id=msg_01LYDPCEFPj1HHk85kT6mKNz…

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