dmarc_summary

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

With no annotations provided, the description bears the burden of disclosing behavior. It does convey that the tool reads stored aggregate reports and produces a summary, which implies a read-only operation. However, it does not mention potential side effects, data freshness, authentication requirements, or what happens if no reports exist. The listed output fields add some transparency but leave gaps.

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 description is a single, focused sentence that front-loads the main purpose and efficiently lists the three key output components. Every word adds value, with no repetition of the tool name or irrelevant detail. It is appropriately concise.

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 that there is no output schema, the description adequately conveys what the tool returns (pass rate, top sending sources, disposition totals). For a summary tool with three optional parameters, the description covers the core purpose and outputs. It could mention edge cases like empty results or date range behavior, but these are largely covered by the schema. The lack of usage context slightly reduces completeness, but overall it is sufficient.

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%, so the schema fully documents the 'to', 'from', and 'domain' parameters. The description adds no parameter-specific meaning beyond mentioning 'stored aggregate reports', which is already implied by the schema. Per the baseline rule for high schema coverage, a 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 clearly identifies the tool as producing a DMARC compliance summary over stored aggregate reports, and explicitly lists the output contents (pass rate, top sending sources, disposition totals). It is distinct from sibling email tools that focus on sending, templates, or general stats. However, the description lacks a strong active verb, using a noun phrase instead of 'Calculate' or 'Get', which is a minor weakness.

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 provides no guidance on when to use this tool versus alternatives. It does not mention any prerequisites (e.g., having stored aggregate reports) or contrast with sibling tools like get_stats. The context of DMARC summaries is implicit from the name but not explicitly articulated.

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