Qibla direction

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

Annotations already cover read-only, idempotent, non-destructive, open-world behavior, so the description adds real value by disclosing data provenance (computed from coordinates via great circle, not sourced from Time.ir) and by disambiguating true north from magnetic north. Remaining gap: it does not state the units for the returned distance.

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, front-loaded sentences with no filler. Minor redundancy: the true-north reference is stated twice (in the parenthetical and again in the final sentence), which could be tightened.

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 no output schema, the description carries the burden of describing returns, and it does name both outputs (direction in degrees and distance) plus their method. It falls short only on the distance unit and on ambiguity behavior when a city name matches multiple entries.

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%, so the parameter baseline is 3, and the description earns an increment by adding a constraint the schema lacks: the city must be Iranian. It adds nothing further about city-id/province resolution, which the schema already handles.

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 and resource ("Get the qibla direction ... and distance"), scopes it to an Iranian city, and defines the bearing convention precisely (degrees clockwise from true north). This clearly separates it from date/holiday-oriented siblings and from ti_prayer_times.

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 domain restriction to Iranian cities implies when the tool applies, but there is no explicit when-to-use/when-not guidance and no sibling is named as an alternative. An agent must infer that this is the qibla tool and not, say, an extension of ti_prayer_times.

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