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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds genuinely useful non-obvious context: the endpoint is a POST but is "a read", which preempts an agent mistaking the HTTP verb for a mutation. It notes performance ("Fast") but says nothing about result limits or cost on large datasets.

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 sentences plus an endpoint reference; the output contents are front-loaded in sentence one and the routing advice in sentence two. No filler or restated title.

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?

With 17 optional parameters and no output schema, the description carries the return-shape burden well by naming the exact summary fields (first/last date, counts by forms/resources/locations/users) and by clarifying the read-only nature of the POST endpoint. Nothing an agent needs to call it correctly is missing.

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% and the schema documents far more than the description does — date_type enum semantics, start/min_ago mutual exclusivity, time_zone_offset, identifier pairing. The description only says "records matching the filters" without adding any parameter meaning, so the baseline 3 for a fully documented schema is correct.

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 (summarize records matching filters) and enumerates exactly what the summary contains: first/last date plus counts of forms, resources, locations and users. It also distinguishes itself from the sibling it is not, naming safetychain_search_records explicitly, so an agent can route without opening either schema.

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 size a request before safetychain_search_records" gives clear when-to-use context and names the alternative. It stops short of an explicit when-not clause (e.g., don't use this to retrieve record contents, don't replace search), so it lands at clear-context-without-exclusions rather than full 5.

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