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

Annotations already establish readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds non-obvious context beyond that: the signature is owner-bound, it 'Never publishes,' and documentJson/media must be preserved during a complete replacement — a real behavioral caveat for the subsequent update.

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, each carrying distinct information (when to use, read-before-edit workflow, preservation warning), with the purpose front-loaded. The telegraphic phrasing is efficient but occasionally clipped.

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?

An output schema exists, so return values need not be explained. Given trivial schema complexity, the description covers the operational essentials — read-only nature, owner binding, no-publish guarantee, and the replacement caveat — leaving only the ID format unaddressed.

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 0% and the single signatureId parameter is undocumented in the schema. The description only indirectly hints at the value's meaning via 'owner-bound auto-signature,' offering no format, ID-source, or lookup guidance to compensate for the coverage gap.

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 ('Read') and resource ('owner-bound auto-signature'), and the opening clause scopes it to 'managing post auto-signatures.' It implicitly distinguishes itself from write siblings like update_signature, but never names them explicitly, so it stops short of a top score.

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?

It states a clear usage context: 'Read this owner-bound auto-signature before editing it,' which establishes a read-before-write workflow. It does not, however, name alternatives such as list_signatures or preview_signature or state exclusions, so the routing guidance is good but not exhaustive.

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