jef-mcp

Ask Jef to rate something

jef_score

Read-onlyIdempotent

Convert subjective descriptions into a consistent 1-10 rating. Get a deterministic numeric verdict for outfits, plans, or excuses when a score is needed.

Instructions

Rate something from 1 to 10. Use this when the user wants a number put on something subjective, such as an outfit, a plan, or an excuse. The number is arbitrary and deterministic, so the same description always scores the same.

Input Schema

TableJSON Schema

Name	Required	Description	Default
`thing`	Yes	What is being rated, described in the user's own words.

Output Schema

TableJSON Schema

Name	Required	Description
`kind`	No	Which decision shape was used.
`answer`	Yes	A score written as "7/10".
`blocked`	Yes	True when the input contained profanity, slurs or sexual content. Nothing was stored or echoed. Do not retry.
`ranking`	No	The options in order, best first. Null unless the shape was order.
`cost_usd`	No	Always 0. There is no billing.
`thoughts`	No	Always 0.
`escalated`	Yes	True when the input touched health, harm, money, law or safety. Tell the person to ask a human. Do not rephrase and retry.
`confidence`	Yes	0.84 to 0.99 normally, exactly 0 when escalated or blocked. It is not calibrated and means nothing.
`latency_ms`	No	Negative. Jef answers before you ask.
`tokens_read`	No	Always 0. The input is hashed, not read.
`probabilities`	No	One entry per option, percentages summing to 100. Null unless the shape was pick.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.4.7Sep 19, 2026

TDQS

A4.5/5.0

Behavior4/5

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

The description adds useful behavioral context beyond annotations by explaining that the score is 'arbitrary and deterministic' and that identical descriptions always receive the same score. This supplements the idempotentHint and readOnlyHint annotations with a meaningful user-facing behavior, though the deterministic aspect is somewhat implied by the idempotent annotation already.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is compact, front-loaded with the core action, and every sentence earns its place. The purpose, usage context, and key behavioral caveat are all covered in three concise sentences with no filler or redundant detail.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the low complexity (single parameter), rich annotations, and presence of an output schema, the description is fully sufficient. It explains what to input, how the tool behaves, and when to use it, leaving no critical gaps for an agent to select and invoke the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

With 100% schema coverage, the parameter is already well documented. The description adds value by specifying the kind of content expected ('something subjective') and providing examples (outfit, plan, excuse), which clarifies the scope of 'thing' beyond the schema's generic 'what is being rated.'

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Rate something from 1 to 10') and the exact resource/subject being rated, distinguishing it from siblings like jef_flag or jef_yes_no by specifying a numeric 1-10 subjective rating. The verb and resource are specific and unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly says 'Use this when the user wants a number put on something subjective' and gives concrete examples (outfit, plan, excuse), providing clear conditions for use. However, it does not explicitly mention when not to use it or name alternative tools, so it falls just short of full routing guidance.

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

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