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

Annotations already cover read-only, idempotent, non-destructive, closed-world. The description goes beyond them by disclosing result ordering (newest first) and that aggregated totals per project and per day are included, which sets expectations an agent can't get from the hints alone.

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 short sentences, front-loaded with scope and return shape before the usage hint. No filler and nothing repeated from the name or title.

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?

With an output schema handling return values and annotations handling safety, the description covers all the behavioral context an agent needs to call this correctly. Only minor gaps remain, such as any practical limit on the date span or how an unknown project string is treated.

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 coverage is 100%: from/to inclusivity and the project id-or-name format are already documented in the schema. The description only echoes 'inclusive' and the optional project limit, adding no syntax or matching detail, so the 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?

States a specific verb (list) and resource (time entries) plus the exact scope and return shape: date-bounded, inclusive, newest-first, with per-project and per-day totals, optionally filtered to one project. That combination of ordering/aggregation semantics cleanly separates it from siblings like project_totals, annual_report, and get_running_timer.

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?

Gives concrete trigger scenarios ('what did I log last week', checking a day before adding time), which maps the tool to real intents. It stops short of naming alternatives or exclusions (e.g., when to prefer project_totals or merge_entries instead), so it is clear context without routing.

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