tokcost is pre-1.0. Security fixes land on the latest release; there are no maintained backport branches.

Please do not open a public issue for a security vulnerability.

Report it privately through GitHub's private vulnerability reporting for this repository. If that isn't available to you, contact the maintainer directly through their GitHub profile.

Please include:

• What the issue is and where in the code it lives
• Steps to reproduce, ideally with a concrete input
• What an attacker could achieve with it

You can expect an initial response within about a week. If the report is confirmed, I'll work on a fix and credit you in the release notes unless you'd rather stay anonymous.

Knowing what tokcost does and doesn't do makes it easier to judge whether something is a real issue:

tokcost makes zero network calls. Not for pricing, not for telemetry, not for vocabulary downloads — everything it needs is compiled into the binary. Any observed outbound connection from tokcost itself is a genuine bug and worth reporting.

tokcost has zero runtime dependencies. The [dependencies] section of Cargo.toml is empty, so the supply chain is this crate plus the Rust standard library. There is no transitive dependency tree to audit.

tokcost reads, but never writes, the files you point it at. The counting path opens inputs read-only. It does not create, modify, or delete files.

No unsafe code. The crate is entirely safe Rust.

These are the interesting surfaces for review:

• File and stdin content is treated purely as bytes to tokenize. Invalid UTF-8 is replaced lossily rather than rejected, and content is never evaluated, executed, or interpreted as anything but text.
• TK_PRICES is parsed from the environment. Malformed entries are skipped rather than failing the run; values are parsed as plain floats.
• tokcost meter -- <command> spawns a child process. The command is taken from your argv and executed without a shell (std::process::Command passes arguments directly), so shell metacharacters in arguments are not interpreted. tokcost applies no sandboxing to the wrapped command — it runs with your full privileges, exactly as if you had run it yourself.
• Terminal output may include ANSI escape sequences for color, but only when stdout is a TTY. Content read from input files is never echoed back to the terminal, so a file containing escape sequences cannot use tokcost to manipulate your terminal.

• The accuracy of the pricing table (it's a dated snapshot — see the README)
• Token counts that differ from a provider's own counter (report those as regular bugs; they're valuable, just not security issues)
• The behavior of a command you explicitly wrap with tokcost meter