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

With annotations already covering the safety profile (readOnlyHint=true, destructiveHint=false, openWorldHint=false), the description adds substantial non-obvious behavior: expired countdowns and inactive streaks are omitted, sobriety/streak trackers persist at day 0 after reset, event-backed trackers are merged with the trackers table, and current_value is derived per tracker type (days, days left, counter total) with last_event_date. It also discloses auth requirements (OAuth or scoped credential) and cost ($0.10). This is rich context well beyond the annotations.

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?

Every clause carries information (filtering, merge behavior, value derivation, pagination, auth, cost) with no filler, but the sentence structure is dense and the core purpose is not front-loaded ahead of the filtering rules. It is efficient yet slightly overloaded for a one-parameter read tool.

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?

An output schema exists, so return shapes need not be explained, and the description still covers the essentials an agent needs: filtering semantics, merge behavior, current_value derivation, pagination via limit/total/truncated, auth requirement, and cost. For a single-parameter read tool, nothing material is missing.

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 100% for the single `limit` parameter, and the schema already documents the 1–200 range and default of 50. The description restates the default/max and adds the useful note that get_context_pack's active_trackers keeps 6, but provides no syntax or semantic detail beyond the schema. Baseline 3 is appropriate.

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 clear verb and resource ("Returns up to `limit` trackers") and scopes it tightly to authenticated live trackers, omitting expired countdowns and inactive streaks. It hints at sibling differentiation by noting get_context_pack's active_trackers keeps only 6, but does not explicitly distinguish itself from reset_tracker or other tracker-adjacent tools. The purpose is clear but not front-loaded, opening instead with filtering rules.

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 implied rather than stated: the description explains filtering behavior and mentions get_context_pack's 6-tracker limit, which hints at when to prefer that tool, but never says explicitly when to call get_trackers versus alternatives. There are no exclusions or prerequisites framed as guidance. This is minimum-viable context for routing.

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