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

With no annotations, the description carries the full burden and does well: it discloses the payment model (0.001 USDC via x402 or API key, auto-pay behavior) and which auth paths are free. It could still say more about result ordering or what happens when filters match nothing, but the auth/cost disclosure is exactly the kind of context annotations would otherwise provide.

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?

The capability and usage sentence is front-loaded, and the bracketed access note is dense but every clause (cost, header, auto-pay, free-with-key) is decision-relevant. Slightly parenthetical-heavy but no filler.

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 five-parameter, zero-required list tool with no output schema and no annotations, the description covers purpose, filter dimensions, return contents and payment/auth requirements. Missing only minor operational details like ordering and empty-result behavior.

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 five parameters are already documented with defaults, caps and enum-like values. The description only restates the filter dimensions (regime band, role, category) without adding syntax or edge-case behavior, 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?

States a specific verb and resource (list trading signals) and enumerates the returned fields (names, types, short descriptions). It implies a browse-vs-search distinction against siblings like search_signals but never names an alternative explicitly, so differentiation is only partial.

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?

"Use it to browse the catalogue, or narrow it by regime band, role or library category" gives a clear when-to-use and maps each filter to an intent. It stops short of naming when NOT to use it or pointing to search_signals/match_signals as alternatives.

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