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

With no annotations, the description carries the full burden, and it does substantial work: it discloses the trust-block contents, honesty grades, and the HTTP 402 behavior of dormant priced doors with empty accepts[] until payment rails are live. It does not mention pagination, rate limits, or exact response shape, but the core behavior is clearly disclosed.

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 description is relatively dense but front-loaded with the core purpose ('The Axion Doors registry') and packs useful behavioral detail into a compact space. It is not perfectly concise due to the long first sentence, but every clause contributes information.

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?

There is no output schema, so the description must convey what the tool returns, and it does: trust blocks with four named fields, free endpoints, MCP servers, and dormant priced doors. It is complete enough for an agent to select and invoke the tool, though the ambiguous 'one field' phrase and absence of an explicit return envelope keep it from being fully complete.

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 baseline is 3. The description adds 'Filter by zone', which mirrors the schema, but does not meaningfully enrich either parameter. The phrase 'ask for one field across every zone' is ambiguous and does not map to any documented parameter, so it does not add clear value beyond the schema.

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 identifies the tool as a registry of every machine-callable 'door' (endpoint/tool) and explicitly says it also lists free endpoints, MCP servers, and dormant priced doors. The verb 'lists' is explicit, the resource is well-scoped, and this is clearly distinct from the specific sibling lookup tools.

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 gives clear context for when to use the tool: before trusting results from other tools, an agent should read the trust block it provides, and it is the place to discover free endpoints and dormant doors. It does not explicitly name sibling alternatives or state when not to use it, so it stops short of a 5.

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