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

With no annotations provided, the description carries the full burden and does disclose 'Read-only: no side effects' plus the exact return shape and keys. It stops short of stating auth requirements, caching, or rate limits, so it is not exhaustive, but it covers the key behavioral facts for a zero-parameter GET.

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?

It is front-loaded with the purpose, then usage, exclusion, side effects, and return shape in a logical order. There is mild redundancy: the payload keys listed in the opening sentence are repeated verbatim in the 'Returns' sentence, which costs a little length without adding information.

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 zero-param read endpoint with no output schema, the description supplies the canonical path, the full set of returned keys, the read-only guarantee, and sibling routing. An agent has everything needed to select and call it 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 tool takes no parameters, which is the baseline-4 case; the description confirms 'No parameters.' Nothing further is needed, and no meaning is missing.

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 ('Get the Designesy agent discovery document (/.well-known/agent.json)') and enumerates the payload contents. It distinguishes itself from siblings by naming designesy_catalog and designesy_contract as the alternatives for narrower needs.

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?

Explicitly gives the use condition ('when you are integrating with or enumerating Designesy as a machine agent and need the canonical discovery/manifest endpoint rather than one specific contract') and an explicit 'When NOT to use' clause routing to designesy_catalog for the package list and designesy_contract for the contract.

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