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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, openWorldHint=false, so the restated 'Read-only: no side effects' is redundant. What the description does add is substantive: it discloses the relative payload size (over ten thousand characters vs a few thousand for the sibling) and, critically, that sections written as steps or prompts are replaced by a one-line marker and listed in omitted_sections — a non-obvious transformation of the returned content that no annotation conveys.

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 long, but the front-loaded purpose sentence and the labeled 'When NOT to use' and 'Returns JSON' blocks make it scannable, and each clause carries information. Slight redundancy appears where 'Read-only: no side effects' repeats the annotations, but overall the sentences earn their place.

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?

There is no output schema, so the description carries the return-value burden, and it discharges it with an explicit JSON shape including field names and the meaning of omitted_sections. Combined with the usage routing and size expectation, an agent has everything needed to select 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, which is the baseline-4 case. The description confirms this explicitly ('No parameters.'), matching the empty input schema with no ambiguity.

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 /llms-full.txt brief') and enumerates the content scope: authority, discovery endpoints, topics, packages with links, standing rules, anti-patterns. It explicitly differentiates itself from the sibling designesy_llms_txt (short brief) and designesy_contract, so an agent can route without opening any 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?

It gives explicit when-to-use ('when the short brief from designesy_llms_txt is not enough') and a labeled 'When NOT to use' section naming two alternatives and the conditions that select them (quick orientation -> designesy_llms_txt; the contract itself -> designesy_contract). Nothing is left to inference.

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