check_snapshot

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, and the description reinforces this with 'only reads that file and sends nothing', adding the useful detail that nothing leaves the machine. However, it never states what the check returns (match/mismatch boolean, error on missing file), which is the key behavioral fact for a verification tool with no output schema. Adequate but with a real gap.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three short sentences with the core operation stated first, the side-effect guarantee second, and workflow routing last. Nothing is redundant and every clause carries information.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a two-parameter verification tool with no output schema, the missing piece is the result contract: whether success means a boolean, a diff, or an error, and what happens if the file doesn't exist. The description is otherwise sufficient to invoke the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and both parameters document their format themselves ('sha256: followed by 64 hex digits', 'absolute or relative to this session's folder'). The description adds no format or edge-case detail beyond the schema, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource: verify that a local file's sha256 matches a snapshot's hash. The scope ('in this session's folder') and the read-only nature are stated up front, and it ties itself to the read_inbox/send_message workflows by name. It stops short of explicitly contrasting itself with siblings like read_diff, but the purpose is unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly says 'Use it for the --check step of the read_inbox and send_message descriptions', which tells the agent exactly where this tool belongs in a workflow. It doesn't state when NOT to use it (e.g., instead of read_diff or when the file hasn't been written yet), so it falls short of a 5.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.