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

With no annotations, the description carries full behavioral burden. It usefully discloses trigger semantics (fires on new matching openings) and cost ('Free.'), which is real added context, but omits auth requirements, delivery/retry behavior, whether duplicate registrations are deduped, and how to manage or remove the webhook.

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, purpose front-loaded, and the one-word 'Free.' earns its place as a cost signal. The criteria enumeration is mildly redundant with the schema but remains compact and readable.

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 two-parameter webhook-registration tool with no annotations and no output schema, the description covers purpose, trigger, criteria shape, and cost, but leaves gaps around authentication, registration response (e.g., an ID needed to unsubscribe), and duplicate/retry handling that an agent would want before calling.

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 both url and criteria are already documented. The description restates the criteria fields ({state, city, signal_type, min_opening_score}) but adds no constraints such as accepted state/city formats, signal_type values, or valid min_opening_score range. Baseline 3 is appropriate.

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 concrete verb (register) and resource (webhook) plus the exact trigger condition: a new matching venue opening in an area. It implicitly distinguishes itself from the query-style sibling new_openings by being the push/registration mechanism, but never names that sibling or contrasts with it explicitly.

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 case is implied by 'fires when a new matching venue opens,' suggesting ongoing notification rather than one-shot lookup. However there is no explicit when-to-use instruction, no mention of how it differs from new_openings/venue_signals, and no stated prerequisites for registering a webhook.

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