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 usefully adds the return shape and notes the underlying call is POST agents/detail — valuable because a mutating-looking verb backs a read-only operation. It does not say what happens when the id is unknown.

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?

A single dense clause with the return payload front-loaded and the conditional flag parenthesized at the end; nothing is wasted. It borders on terse for a tool with a nested response, but every element earns its place.

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 no output schema, the description carries the burden of describing the response, and it does list the main sections returned. Gaps remain around error behavior for a bad id and whether agencies/addresses are always present, but for a two-parameter read tool it is largely sufficient.

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 coverage is 50%: include_activities is already documented in-schema, and agent_id has no schema description. The description's mention that activities appear only when include_activities is true largely restates the schema, adding little on format or validity for agent_id.

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 — fetch a single agent by id — and enumerates the payload (agencies, addresses, custom fields, optional activities). That distinguishes it in spirit from the search_* siblings, though it never names agencybloc_search_agents as the alternative.

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 id' signals you must already have an agent id, which steers away from the search tools. There is no explicit when-to-use/when-not statement and no mention of what to do when only a name or email is known.

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