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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds genuinely new context beyond the annotations: the per-call cost of $0.002 USDC via x402, which matters for an agent deciding whether to invoke it. It does not discuss pagination or how 'newest' is ordered/refreshed.

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 short sentences, zero filler, with the identity/scope stated first and the billing caveat second. Nothing is redundant with the title or schema.

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 single-parameter feed with an output schema, the definition covers what the tool returns (newest econ submissions) and the unusual payment requirement. The only minor gap is the absence of routing guidance relative to arxiv__recent and arxiv__search, which a family this large would benefit from.

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?

There is a single optional 'limit' parameter with 100% schema description coverage ('Results, max 50 (default 25)'), so the schema already carries the meaning. The description adds nothing about the parameter, which is the expected baseline when the schema does the heavy lifting.

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 states a specific resource and scope: 'newest arXiv submissions in econ (Economics)'. That is enough to separate it from the many sibling category feeds (recent-cs-ai, recent-quant-ph, etc.) and from arxiv__search, but it does not explicitly name which sibling it supersedes or how it differs from arxiv__recent.

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 by the category label - an agent can infer this is for browsing the latest econ papers rather than searching. There is no explicit when-to-use statement, no exclusion (e.g. use arxiv__search for topical queries), and no guidance on when to prefer arxiv__recent with an explicit category argument.

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