backfill_recurring_instances

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

Despite no annotations, the description discloses key behaviors: it only processes a trailing window, does not enter cash-flow projections, does not fabricate payments, and uses the normal reconciliation matcher. This gives the agent good understanding of side effects and limitations.

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?

Three sentences with no wasted words. The first sentence immediately states the core purpose, followed by clarifying constraints (forward-only, no fabricated payments). Efficient and well-structured.

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?

Given no output schema and 3 parameters, the description provides sufficient high-level context: what data it processes, what it reconciles against, and what it does not do. Missing details like error handling, performance implications, or idempotency, but overall adequate for a backfill tool.

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?

The description mentions a 'trailing window' which loosely relates to as_of_date and lookback_days, but does not explicitly define any parameter semantics. With 0% schema description coverage, the description should compensate but fails to add meaningful details beyond what the schema already shows (names, types, defaults).

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 clearly identifies the tool's verb (materialize, reconcile), resource (past-due instances for recurring obligations), and purpose (to answer whether recurring charges cleared). It distinguishes itself from siblings by specifying its backward-looking and forward-exclusion behavior.

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 description implies usage for reconciling past recurring charges and affects the digest, but it does not explicitly state when to use or when not to use this tool versus alternatives like reconcile_obligation_instances or list_matched_obligation_instances. No exclusions or prerequisites are provided.

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