Inspect a zip, part, file or folder

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

Annotations already declare readOnlyHint=true and openWorldHint=false, and the description reinforces this with "Read-only" while adding substantive detail about what each inspection yields (entry counts, oversize entries, estimated part count, part n of N, present/missing parts, readiness to rebuild). With no output schema, this per-type return description is genuinely load-bearing; only error/nonexistent-path behavior is unaddressed.

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?

Front-loaded with the read-only guarantee, then organized as four parallel "For a X:" clauses, each carrying distinct information with no filler. Slightly longer than minimal, and the opening "Read-only" restates the annotation, but no sentence is wasted.

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?

Given four optional parameters, no output schema, and a multi-modal input, the description does the work of documenting return content per input type, which is the main gap it needed to fill. Missing only edge-case behavior (invalid/missing paths, what happens when the zip is encrypted or malformed) to be fully complete.

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 description coverage is 100% and the schema already documents path, max_mb, preset, and max_bytes in far more depth than the description does. The description adds only indirect context by referencing max_mb in the part-count estimate; it never explains presets or max_bytes, so it does not go beyond the schema. Baseline 3.

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 and resource (inspect a path) and then enumerates exactly what is reported for each input type: zip, AgentParcel part, folder, plain file. This makes it trivially distinguishable from siblings like split_zip, rebuild, and verify, which act on the same resources.

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?

"Look at a path before splitting or rebuilding" gives a clear when-to-use context that ties it to split_* and rebuild. It also states the hard constraint that paths must be absolute. It does not explicitly contrast with verify (the other read-ish sibling) or say when not to use it, 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.