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

With no annotations, the description carries the full burden of behavioral disclosure. It explains the one-sided nature of friendships, returns both directions, and defines outgoing vs. incoming rows. This reveals non-obvious behavior beyond the name and schema, though it does not cover error cases, pagination, or auth requirements.

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 well-structured, front-loaded with the core purpose, and uses bullet points to clarify the two output directions. Every sentence contributes, including the formula for computing mutual friends, with no filler.

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 one-parameter read tool with no output schema, the description provides the essential information needed to call it correctly and interpret its results. It explains the return structure, the directionality, and the relationship to write counterparts, making it complete for an agent.

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% for the single address parameter, but the description adds meaning by defining how 'address' is interpreted in the graph: as the central node that can appear as friender or bap_id in outgoing/incoming rows. This goes beyond the schema's generic 'BSV address to look up.'

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 states a specific verb and resource ('Get the friend graph for a BSV address') and clearly defines the output as two directional lists. The explicit mention of one-sided friendships and the link to peck_friend_tx / peck_unfriend_tx distinguishes this tool from sibling tools without ambiguity.

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?

It explicitly positions itself as the 'Read counterpart to peck_friend_tx / peck_unfriend_tx,' telling the agent when this read tool is appropriate instead of mutation tools. It also explains that mutual friends must be computed by the caller, giving a clear use-case. It does not explicitly list exclusions relative to every sibling, but the key alternative is covered.

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