Special characters are not indexed in Jira Cloud so they cannot be searched is correct.

Jira Cloud does not index many punctuation and special characters so queries that look for literal brackets or similar characters will not return results. The indexed tokens omit those characters and the text search operator cannot match the raw punctuation. Therefore you cannot reliably search for the literal string [CodeSchool] using JQL.

summary ~ "\[CodeSchool\]" is incorrect because escaping the brackets in a text search does not force Jira Cloud to index those characters. Escape sequences cannot make unindexed punctuation searchable.

summary = "[CodeSchool]" is incorrect because the equals operator performs exact matches and it will not match when the punctuation is not indexed. The equality operator is also not suitable for free text searches with punctuation.

summary ~ "[CodeSchool]" is incorrect because searching with the tilde and including the punctuation will not find the literal brackets. The brackets are treated as special characters and are not part of the indexed text in Cloud.

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