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

Annotations already declare readOnlyHint/idempotent/non-destructive/closed-world, so safety is covered. The description adds non-obvious behavioral nuance: that certain tiers can no longer be STARTED yet their finished runs persist in the vault, which meaningfully affects interpretation of results. Pagination behavior is omitted but cursor is documented in schema.

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?

Purpose is front-loaded, followed by parameter clarifications in a logical order. Dense but each clause carries meaning; only minor redundancy with 'premier = Deep' appearing again in the schema.

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 read-only list tool with no output schema, 100% schema coverage, and zero required params, the description covers the semantic quirks an agent needs. Return field shape is not described, but no output schema exists to defer to, leaving a small gap.

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 — explaining that project_id 'none' means unfiled, that status accepts comma-separated values, that tier is a historical filter accepting deprecated-start tiers, and that 'premier' surfaces as 'Deep'. That is genuine value beyond the schema text.

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 (list) and resource (research runs) with a scoping qualifier ('that accumulated evidence in this workspace vault'). It is clearly distinguishable from siblings like run_status (single run) and list_projects/list_notes/list_sources (different resources).

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?

The filtering semantics imply how to narrow results, but there is no explicit 'use this when' guidance or an alternative named (e.g., run_status for a single run). A reader has to infer that this is the multi-run enumeration tool.

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