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

Annotations already declare readOnlyHint=true, so the safety profile is established. The description adds value by noting 'free, no key needed' — a behavioral affordance (no auth required) not captured in the annotations. It also scopes the search domain (Exchange capabilities for rent), which helps the agent understand what results to expect. Description is consistent with annotations.

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, no wasted words. Every phrase earns its place: the purpose, the domain scope with concrete examples, and the key affordances (free, no key) are all packed efficiently. This is a model of conciseness for a simple single-parameter tool.

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 simple search tool with one well-documented parameter, readOnlyHint annotation, and no output schema, the description is largely sufficient. It covers what's searched, the content domain, and access requirements. The only gap is query semantics (how matching works) and what result format to expect, but these are minor for a search tool of this simplicity.

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 coverage is 100%, with the single 'query' parameter described as 'what you're looking for'. The description's mention of 'memory, reasoning, safety, images, commerce' adds domain vocabulary that hints at valid query types, giving slight value beyond the schema. However, it doesn't clarify match semantics (fuzzy vs exact, keyword vs natural language) which would help an agent formulate queries effectively.

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 clearly states what the tool does: search the MeshMarket exchange for rentable capabilities. It specifies a verb (search), a resource (MeshMarket exchange), and the scope (capabilities agents can rent across memory, reasoning, safety, images, commerce). The main gap is that it doesn't explicitly differentiate from siblings like mesh_discover or merchant-discovery, though the exchange-specific search intent is reasonably distinct.

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?

The description implies when to use it ('search for capabilities agents can rent') but provides no explicit exclusions or alternative recommendations. Context like 'free, no key needed' gives useful usage context, but there's no statement about when NOT to use this versus mesh_discover, mesh_delegate, or other discovery tools in the sibling set.

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