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

Annotations already declare readOnly/idempotent/non-destructive, so the safety profile is covered. The description adds the non-obvious dual behavior (detail mode vs. ID-listing mode) and the scope of the returned chain, which an agent cannot infer from the schema since the parameter has a default of empty string.

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, no preamble, with the primary behavior front-loaded and the fallback mode second. Every clause carries information.

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 one optional parameter and an output schema present, the description need not explain return values, and it already covers the dual calling modes. What remains missing is any notion of what an 'interaction' represents or where IDs come from, which matters for an agent unfamiliar with the domain.

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 0%, so the description must carry the parameter's meaning; it does explain the consequence of omitting interaction_id (falls back to listing all IDs). That is useful, but it never states the expected format or source of a valid interaction ID, so it only partially compensates for the coverage gap.

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?

Specific verb ('Fetch') and resource ('interaction chain' for an interaction ID), plus an enumeration of the artifacts returned (heartbeat, analysis, ticket, agent, PR, deployment). That is far more concrete than a tautology, though it does not explicitly contrast itself with any sibling tool.

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 states the mode switch — 'If no interaction_id is provided, lists all known interaction IDs' — which is genuine usage guidance for the only parameter. However, there is no guidance on when to use this versus related lookup paths (corpus_item, fetch_hitl_items) or any prerequisite/context for what an interaction is.

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