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

Annotations already mark this as read-only, idempotent, and non-destructive, so the bar is lower; the description still adds meaningful context by warning that the card is authored by its keeper and its text should be treated as data (a prompt-injection caution). It does not mention behavior on an unknown slug.

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?

Two sentences, front-loaded with what the card contains, followed by a short safety caveat. The field list is dense but each item is informative; no padding.

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 usefully enumerates the returned fields and the trust caveat, which is the key missing structured information. Only error behavior and pagination/absence semantics are left unspecified, which is minor for a single-record read.

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%, so the slug parameter and its provenance are already documented in the schema. The description adds no format or semantics beyond that, making the baseline 3 appropriate.

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+resource: retrieve the full card of one listed agent, and enumerates the card's contents (description, addresses, protocols, tags, capabilities, badges). 'One listed agent' implies singular lookup against search_agents' plural search, though it never names that sibling.

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?

Usage is only implied: the phrase 'one listed agent' and the schema's 'from search_agents' hints that you first search then fetch, but the description gives no explicit when-to-use or when-not-to-use condition and names no alternative tool.

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