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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description goes further by disclosing the Phase 114 clamping behavior, the fact that leading $0 months are dropped, and the two metadata fields (clamped_to_first_activity, requested_months) returned. This is genuinely non-obvious behavior an agent could not get from the structured fields.

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 purpose sentence is front-loaded and the return/metadata notes earn their place, but the 'Phase 114 —' internal roadmap reference is developer-facing noise that adds little for an agent. Conventional Args/Returns block is slightly redundant with the prose above it.

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 single-parameter read tool with no output schema, the description covers what it returns, the metric breakdown, and the clamping metadata, which is enough to call and interpret it. Missing only pagination/size caveats and tighter parameter bounds.

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%, and the description supplies only 'months: Number of months (default 12)'. It adds conceptual meaning via the 12-month example and clamping narrative, but does not state bounds, allowed ranges, or edge behavior for extreme values, so compensation for the coverage gap is partial.

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 names a specific metric (savings rate) and granularity (monthly over time), and clarifies sub-fields (income, expenses, net, savings rate percentage). It also ties itself to the intent 'is my savings rate improving?'. It references the period summary for the clamping logic but does not strongly disambiguate against close analytics siblings like get_financial_ratios or get_cash_flow.

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 only implied via the example question ('is my savings rate improving?'), which suggests the analytics intent. There is no explicit when-to-use/when-not guidance and no named alternative for related trend questions, so selection against the many sibling analytics tools is left to inference.

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