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

Annotations already declare readOnly, idempotent, non-destructive, non-openWorld, so the safety profile is covered. The description adds real behavioral context beyond that: the data is precomputed, what each return mode contains (taxonomy counts, roots, multi-parent nodes, weakly-connected components; depth, betweenness, fan-in/out per node), and that a full tier adds a held analyst layer. It does not discuss staleness/refresh or auth, which keeps it from a 5.

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?

Front-loads the core purpose and the omit/pass decision before the sibling routing and filter notes. Dense but every clause carries information; the metric enumerations are long but necessary given no output schema. Minor density cost keeps it off a 5.

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 return-value burden and does so fully (enumerated metrics per mode plus tier distinction), while annotations handle safety. An agent has everything needed to call and interpret this tool.

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 100%, so baseline is 3, but the description goes further: it explains the presence/absence semantics of node_id (omit = whole-graph, include = single node with example 'E34') and clarifies that class/cc_type/min_reach act as node filters returning matching nodes. That is meaningfully more than the raw 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?

Names a specific verb (Retrieve) and resource (Coordination Topology), defines the underlying structure (DAG lineage over the parent→child Coordination Connection graph), and explicitly distinguishes itself from two siblings (traverse_coordination, get_event_stack). An agent can route correctly without opening any 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?

Gives explicit branching guidance: omit node_id for whole-graph statistics, pass node_id for single-node metrics, and points to traverse_coordination for actual paths and get_event_stack for an event's value chain. This is textbook when-to-use plus named alternatives.

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