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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, but the description adds real information beyond them: the call costs no credits, triggers no payment, makes no AI call, and is public (implying no auth). That cost/side-effect profile is exactly the kind of context annotations cannot express.

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?

Three short sentences, no filler, with the read-only/public scope front-loaded before the cost caveats. Every clause earns its 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?

For a zero-required-parameter list tool with an output schema, full annotation coverage and 100% schema description coverage, the description supplies the remaining essentials: it is safe, public and free to call. Only the missing sibling routing keeps it from a 5.

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 all four filters (limit, market, capability, seller_agent_id) are already documented in the schema. The description adds nothing about filtering semantics, so the baseline 3 applies.

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 names the verb and resource ('service discovery') and the tool's read-only, public nature, which matches the name nexus_trade_list_offers. However, it never explicitly says it lists offers, and it doesn't distinguish itself from siblings like nexus_trade_my_orders or nexus_discover_agents.

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?

'Public/read-only A2A service discovery' implies a discovery context, but there is no explicit when-to-use statement, no prerequisites, and no routing advice toward or away from the several sibling discovery tools (nexus_a2a_discovery, nexus_discover_agents, nexus_guest_discovery).

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