Midpoint Pictures

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false, and openWorldHint=false, so the description's remaining job is smaller. It does add genuinely useful operational facts that annotations never carry: the POST endpoint, the 10-credit Tier 1 cost, and which four inputs are mandatory. It says nothing about response shape or failure modes, but the cost and required-input disclosures earn above baseline.

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?

It is short and the bracketed metadata is easy to scan for endpoint, required inputs, and cost. But the first line is front-loaded with opaque notation rather than a plain statement of purpose, so brevity comes at the cost of comprehension.

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?

For a 14-parameter, 21%-documented endpoint, the description leaves the caller without enough to call it correctly or distinguish it from neighbouring midpoint tools. An output schema exists, so return values need not be explained, but the unresolved significance of withTnp, cosmogram, and the required-vs-optional split is a real gap.

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 only 21% across 14 parameters, so the description should have compensated, yet it only restates the four required fields already marked required in the schema. Ten optional parameters, including the cosmobiology-relevant withTnp (transneptunian points) and cosmogram flags, the house system, and the sidereal ayanamsa choice, receive no explanation anywhere the caller can see.

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 single content sentence, 'A=B/C structures with sentence form,' is specialist shorthand that never says what the tool computes (a Hamburg School / cosmobiology midpoint picture for a chart moment) or what the caller receives. It gives no verb and no resource framing, and it does not separate this tool from close siblings such as astroway_aspects_midpoints, astroway_aspects_midpoint_trees, or astroway_cosmobiology_transit_midpoints.

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?

There is no when-to-use or when-not-to-use guidance, and no mention of the sibling tools that also produce midpoint or aspect structures. The only routing signal is the group tag '[Cosmobiology / Hamburg School]', which is a taxonomy label rather than a selection rule.

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