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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, and the description reinforces 'Read-only: no side effects' without contradicting them. It adds a genuinely non-obvious behavioral trait: fields written as agent steps (e.g. ingest.steps) are stripped from the returned document and their paths reported in omitted_fields. That disclosure is beyond what annotations convey.

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 purpose and usage before any return detail, and the when-not-to-use clause is placed early where it is most useful. The long enumeration of document fields is verbose but largely earns its place because no output schema exists; a tighter summary of the return shape would read better.

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?

With no output schema, the description carries the return contract itself, naming the output object's fields (kind, source_url, media_type, note, omitted_fields, document) and the shape of the nested document. Combined with the sibling routing guidance, an agent has everything needed to call and interpret this tool.

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 tool takes zero parameters and the description states this explicitly ('No parameters'), which is the correct baseline for a parameterless tool. There is nothing further to disambiguate.

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 concrete verb and resource (get the /.well-known/agent.json discovery manifest) plus its scope (org identity, authority, endpoints, package index, policy, contact, citations). It explicitly contrasts itself with designesy_catalog and designesy_contract, so an agent can route without opening either schema.

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?

Gives both a positive trigger ('when integrating with or enumerating Designesy and need the canonical discovery manifest rather than one specific contract') and an explicit negative trigger with named alternatives for the package list and the contract. Routing is unambiguous.

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