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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds useful behavioral detail by listing the pack components and the recomputable sha256, though it repeats 'Read-only' and omits caveats such as missing stop records or hash verification.

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?

One front-loaded sentence plus a two-word safety note; every clause contributes to scope or contents. There is no wasted preamble.

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 single-parameter read tool with an output schema, the description covers purpose, bundle contents, and safety, while the output schema can carry return structure. The main gap is the unexplained envelope_id, but overall it is 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?

The sole parameter is envelope_id, but schema description coverage is 0% and the description only says 'one envelope' without explaining ID format, source, or whether it must reference an existing envelope. It adds little semantic meaning beyond the schema's property name.

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?

The description gives a specific verb ('Return') and resource ('evidence bundle for one envelope') and enumerates the bundle's contents, so its scope is clear. It does not explicitly contrast with get_envelope or check_spend, but the composite evidence-pack framing makes it reasonably distinguishable.

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?

No when-to-use, when-not, or alternative tool guidance is provided, despite siblings get_envelope and check_spend that could overlap. The 'evidence bundle' wording implies an audit use case, but tool selection remains inferred rather than guided.

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