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

With no annotations provided, the description carries the behavioral disclosure burden. It addresses this by specifying the selection rule (>=12 hex chars), the singular result, and the detailed contents of the response. It does not discuss not-found or ambiguous-prefix behavior, but for a simple getter the described behavior is substantially transparent.

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?

The description is a single dense sentence that front-loads the core selection mechanism and then lists the return payload components. Every phrase contributes useful information with no filler.

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?

This is a low-complexity tool with one fully documented parameter and no output schema, so the description's enumeration of the response contents provides enough context for a competent agent to invoke it. The only minor gap is that it does not state error behavior for no match or an ambiguous prefix, but the hash-prefix rule mitigates much of that ambiguity.

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 description mostly restates what the schema already says about hash being a manifest sha256 full or prefix. It adds the '>=12 hex chars' constraint and clarifies that the tool returns one measurement, but does not significantly go beyond the schema.

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 clearly states this returns a single measurement selected by manifest-hash prefix and enumerates the exact return components (manifest verbatim, per-member results, divergence diagnosis, replication chain, replicate-POST kit). It is easily distinguished from sibling list_measurements because it explicitly says 'One measurement' rather than a listing.

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?

The description implies when to use the tool: when you have a manifest hash or a >=12-character hash prefix and need the full single-measurement record. It does not explicitly name alternatives like list_measurements, but the hash-prefix selection criterion effectively scopes usage.

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