call_summary

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

With no annotations, the description carries full burden. It discloses the critical behavior that without a valid date window, the tool would paginate the entire account history (potentially many pages). This is a key behavioral trait. However, it does not state whether it is read-only or any authorization requirements.

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 efficiently structured with purpose and returns first, then usage guidance, then an important behavioral note. It is concise with no wasted words, though the note could be slightly shorter.

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 the tool's aggregation nature and the presence of an output schema, the description covers purpose, usage, and the crucial caveat about date windows. It does not explain every field in the output, but that is acceptable. It is quite complete for its purpose.

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%. The description adds meaning for 'days' and 'start_date' by stating the requirement for a date window and the default for 'days'. However, it does not explain 'account_id', 'company_id', or 'end_date' format, leaving gaps.

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?

Description clearly states 'Summarize calls over a date window' and enumerates the specific counts returned (total, answered/missed, first-time/repeat callers, total duration, breakdowns by source). This distinguishes it from siblings like list_calls or usage_summary.

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?

Explicitly states it is 'useful for weekly/monthly rollups without pulling every call into context' and warns about pagination without a date window. This provides clear context for when to use, though it doesn't explicitly name alternative tools.

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